As the Obama administration grapples with evidence that chemical weapons may have been used in conflict-torn Syria, officials on both sides of the political aisle urged President Barack Obama Sunday to move towards arming rebels against Syrian president Bashar al-Assad, a position once rejected by a White House reluctant to commit to military involvement in the rebellion.  

But lawmakers also warned that U.S. forces must be careful that weapons do not fall into the hands of radical Islamist groups.  

"Our problem in who to supply is that some of these groups are strong Islamists, Al Qaeda and others," Senate Judiciary Chairman Patrick Leahy said on NBC's Meet the Press. "And we've seen -- like in Libya, Egypt and elsewhere -- that Islamists tend to get the upper hand if they get in there."

"If we know the right people to get them, my guess is we'll get [weapons] to them," he added.

Former House Homeland Security chair Rep. Peter King, a Republican, similarly warned on CNN's State of the Union program that Al Qaeda has "a lot of control within the rebel movement."

"Obviously Assad is evil, and everyone’s interested he go," King said. "But if we are going to arm the rebels, we have to make sure that those arms are not going to end up in the position of Al Qaeda supporters, nor at the end game is Al Qaeda going to be in a position to take over this movement.”

Rep. Tom Cotton, a Republican member of the House Foreign Affairs Committee, expressed optimism on NBC's Meet the Press that "we are moving closer to arming the reform-minded pro-Western rebels."

"This is something that should have been done many months ago," he added, also voicing support for a no-fly zone using aircraft and naval gunfire. 

Former Rep. Jane Harman, who now serves as the head of the Woodrow Wilson International Center for Scholars, told NBC's David Gregory that there's "no chance" that the United States will have "boots on the ground" in Syria but that the complexities of the region's humanitarian and security issues must be addressed  with support for the rebels. 

"This is a big, escalated problem," Harman added. "I wish we had acted sooner."

Obama said last August that the use of chemical weapons in Syria would be a "red line" that - if crossed - would "change my calculus" on military intervention in the region.

“We have been very clear to the Assad regime but also to other players on the ground that a red line for us is [if] we start seeing a whole bunch of weapons moving around or being utilized," the president said at the time. 

A new report Sunday from the New York Times indicated that some Obama advisers were taken aback by that "unscripted" comment.

This story was originally published on Sun May 5, 2013 10:53 AM EDT

President Barack Obama cautioned Tuesday against rushing headlong to take action against Syria’s ruling regime, cautioning that his administration must gather more evidence before involving itself in that country’s civil war.

The president said that while evidence suggested that chemical weapons were used in Syria – thereby crossing the “red line” Obama had established in the Syrian conflict – more details were needed, namely about who used those weapons, and when.

Pablo Martinez Monsivais / AP

President Barack Obama arrives to answers questions during his new conference in the Brady Press Briefing Room of the White House on Tuesday, April 30, 2013.

“When I am making decisions about America’s national security and the potential for taking additional action in response to chemical weapons use, I’ve got to make sure I’ve got the facts,” Obama said at his first press conference in two months.

"And if we end up rushing to judgment without hard, effective evidence, then we can find ourselves in a position where we can't mobilize the international community to support what we do."

The situation in Syria and other issues of national security – a hunger strike at the terrorist detention facility at Guantanamo Bay, Cuba, and the government's response to the terrorist attack at the Boston Marathon earlier this month – have dominated much of the president's agenda over the past month. 

The hunger strike – the military said on Monday that 100 of 166 detainees had participated in the strike protesting conditions at Guantanamo Bay – prompted the president to renew his call for closing the prison. While the president signed an order early in his first term to shutter the facility, lawmakers in both parties have stymied Obama's efforts to achieve that goal. 

"I continue to believe that we’ve got to close Guantanamo. I think it is critical for us to understand that Guantanamo is not necessary to keep America safe," Obama said. "It is expensive, it is inefficient, it hurts us in terms of our international standing, it lessens cooperation in terms of our allies in counterterrorism efforts, it is a recruitment tool for extremists. It needs to be closed."

Moreover, the president pledged to "go back at" the issue, adding that his administration was reviewing ways to achieve its goal of closing the prison, perhaps by returning to Congress for permission. 

The theme of international cooperation, though, recurred throughout Obama's remarks about these tricky foreign policy issues.

The president, for instance, stressed the need for the United States to act in concert with international allies in response to the situation in Syria, and said the U.S. and its partners were already “deeply invested” in trying to find a solution to the situation in Syria.

But Obama was reluctant to specify what actions his administration might take. “By ‘game-changer’ I mean that we would have to rethink the range of options that are available to us,” he said.

A bipartisan group of lawmakers has expressed reluctance to making a U.S. military incursion into Syria, though more hawkish Republicans have called for targeted strikes to help cripple parts of the Syrian military and assist rebels against the Assad regime.

Obama also said he'd worked with Russian President Vladimir Putin on the situation in Syria, but also the intelligence response to the April 15 bombings at the Boston Marathon.

Amid questions about whether the government failed to heed Russian intelligence warnings about the radicalization of the suspects in the bombing, Director of National Intelligence James Clapper ordered a review on Tuesday into the U.S. government's handling of intelligence in the case. 

"When an event like this happens, we want to go back and review every step that was taken," the president explained. "We want to leave no stone unturned. We want to see if, in fact, there's additional protocols and procedures that could be put in place that would further improve and enhance our ability to detect a potential attack."

Slideshow: Syria uprising

Khalil Ashawi / Reuters

A look back at the conflict that has overtaken the country.

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This story was originally published on Tue Apr 30, 2013 10:54 AM EDT

A bipartisan slate of political leaders pondered what role the United States should play in Syria following indications that its besieged leader used chemical weapons in that country's civil war. 

Following the Obama administration's declaration this week that Syrian leader Bashar al-Assad had used chemical weapons against rebels looking to unseat him, lawmakers pondered how to best respond. President Barack Obama had previously called the use of such weapons a "red line" that would prompt a response from the United States.

Sen. John McCain, R-Ariz., a senior member of the Senate Armed Services Committee, urged the president to begin identifying a strategy to secure Syria's stockpiles of chemical weapons should the government fall.

"Be prepared with an international force to go in and secure these stocks of chemical, and perhaps biological, weapons," McCain said on NBC's "Meet the Press."

But, mindful of Americans' war-weariness following nearly a decade of war in Iraq and Afghanistan, McCain cautioned against sending U.S. troops to Syria, warning that it could prompt resentment from Syrians. 

The Arizona senator said in the meanwhile that Obama could establish a no-fly zone in Syria without endangering any U.S. troops. And McCain also called for Obama to further arm rebel groups. 

The White House has been more cautious, explaining this week in briefings to lawmakers that evidence of the use of chemical weapons in Syria is still preliminary, and the government would take more time to gather intelligence. 

"To use potential weapons of mass destruction on civilian populations crosses another line with respect to international norms and international law.  And that is going to be a game changer," Obama said Friday before meeting with King Abdullah II of Jordan.

"We have to act prudently. We have to make these assessments deliberately," the president added. "But I think all of us, not just in the United States but around the world, recognize how we cannot stand by and permit the systematic use of weapons like chemical weapons on civilian populations."

The administration's caution reflects the difficulty in navigating the situation in Syria. A key concern involves identifying which rebels to arm in Syria, and whether there is a risk of those arms being turned back agains the U.S. in the future. 

"My concern is that al Qaeda has more influence among the rebels than it should," said Rep. Peter King, R-N.Y., a key lawmaker who serves on intelligence and homeland security panels. 

But even beyond the national security implications, some lawmakers have said there might be humanitarian justifications to act in Syria.

"I think the United States could play a bigger role in dealing with the humanitarian crisis," said Rep. Keith Ellison, D-Minn., one of two Muslim members of Congress. "I don't think the world's greatest super power, the United States, can stand by and do nothing."

This story was originally published on Sun Apr 28, 2013 9:33 AM EDT

Pool / Reuters

U.S. Secretary of State John Kerry (R) is greeted by U.S. Ambassador Louis Susman, upon his arrival for his first official trip overseas as Secretary, at the Stansted Airport, east of London, February 24, 2013.

Secretary of State John Kerry landed in London, England on Sunday, using his first overseas trip as America's chief diplomat to introduce himself to some of the United States' top allies.

Kerry will visit nine countries over the course of his ten-day trip, meant to be an introductory tour but also with a focus on ending the violence in Syria.

Along with the United Kingdom, Kerry will visit Germany, France, Italy, Turkey, Egypt, Saudi Arabia, the United Arab Emirates and Qatar.

While in Rome, Kerry will participate in the Friends of Syria Conference, an international meeting to address the nearly two years of violence that have ravaged the country since it plunged into civil war.

Leaders of the Syrian opposition, however, have expressed skepticism about the meeting and have indicated they may not attend, despite urgings from the international community.

"The Syrian Opposition leadership is under severe pressure now from its membership, from the Syrian people, to get more support from the international community. And in that context, there is quite a bit of internal discussion about the value of going to international conferences," a senior Obama administration official told reporters traveling with Kerry.

"The point that we're trying to make, and what we are stressing in all of our conversations with them ... is that they have an opportunity in Rome with the meeting that the Italians have offered to host to see the very countries that have been their greatest supporters, and to come and present to all of us how they see the situation on the ground both in security terms, humanitarian terms, and in political terms and economic terms and to make their case for where they are in terms of the support," the official said.

Catherine Chomiak contributed to this report

President Barack Obama warned Syrian President Bashar Assad Monday that the use of chemical weapons by the regime would be "totally unacceptable."

"The world is watching," Obama said.

"The use of chemical weapons is and would be totally unacceptable and if you make the tragic mistake of using these weapons there will be consequences and you will be held accountable," he added.

U.S. officials told NBC News that the Syrian regime had ordered Syria’s military chemical corp to “be prepared.” The officials stressed the directive was not an order to use chemical weapons and did not come from Assad directly, but that order and a considerable increase in activity around Syria’s chemical weapons sites have raised serious concerns.

Syrian state television reported that the Syrian Foreign Ministry denied the country had any plans to use chemical weapons, no matter the circumstances.

The U.S. officials say the fear is that Syrians are at least preparing to mix the precursor chemicals for sarin nerve gas that could be used in artillery shells – but acknowledged it’s not clear that process has begun. 

Once the precursors are mixed, the sarin produced has a relatively short shelf life. In artillery shells, the precursors are packed separately inside the shells and “mixed” immediately before or shortly after the shells are fired.

Despite Obama’s warning that if Syria uses chemical weapons, “there will be consequences,” U.S. military forces have not been put on alert or given warning orders to prepare for any possible military action against Syria. According to a senior U.S. official, there are "plenty of assets in the region which could respond quickly.” 

Earlier, the State Department said the "use or proliferation of chemical weapons" in Syria is a red line for the United States and would result in the administration's taking "necessary steps or actions."

"We are concerned about any move that might signal that they are somehow ready to use those chemical weapons on their own people," spokesman Mark Toner said Monday, adding that the U.S. is concerned that Assad's increasingly beleaguered regime might seek to up the ante in the 20-month-old uprising.

When asked if the chemical weapon stockpiles are secure, Toner said the U.S. is monitoring them, but "it is hard to say, in Syria today, that any stockpile of weapons is secure."

The U.S. is talking to the rebels fighting against the Assad regime about how they should secure chemical weapons that may come into their possession, a senior State Department official said.

A senior U.S. defense official said Monday that U.S. and allied intelligence have detected Syrian movement of chemical weapons components in recent days.

White House press secretary Jay Carney said "the world is watching" Assad and said he'll be held accountable for his actions. Carney declined to say what U.S. contingency plans involved.

The Associated Press and Reuters contributed to this report.

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As President Barack Obama celebrates his election night victory, he faces a second term that presents both immediate and longer-term challenges, some with deadlines that must be confronted in the seven weeks before New Years’ Eve.

And he'll do it with a Senate still in Democratic control and a House of Representatives again ruled by Republicans.

Here's a look at the six splitting headaches awaiting Obama:

Automatic spending cuts
Congress passed and Obama signed into law the 2011 Deficit Control Act which will cut more than $100 billion in outlays in 2013, starting in January. These cuts were intended to be so unpalatable that they’d spur Congress and the president to strike a deficit reduction deal, but the plan seems about to backfire. Congress and the president in 2013 will be getting more deficit reduction than they really want. The director of the Congressional Budget Office, Douglas Elmendorf, said in August that the cuts in spending, combined with scheduled increases in taxes at the year's end would cause “a significant tightening of fiscal policy” which would “probably lead to a recession early next year.”

Taxes going up, by a significant amount – and not just on the rich
The current income tax rates expire on Dec. 31. A popular middle-class tax break, the $1,000-per-child tax credit for each child age 17 and younger, will be cut in half unless Congress and the president take action before the end of the year. The temporary reduction in the Social Security payroll tax is also set to expire. As a result of all this, according to the Tax Policy Center, the average tax burden will increase by almost $3,500 per taxpayer in 2013. In addition, the Affordable Care Act, starting on Jan. 1, imposes a $20 billion tax increase in 2013 on people with incomes above $200,000, or $250,000 for joint filers.

Debt limit
According to the Bipartisan Policy Center, by sometime in February the federal government will reach its borrowing limit, even with the use of extraordinary stopgap accounting measures by the Treasury Department to push back that date. The House Republicans only very reluctantly voted to raise the debt limit in 2011 after the impasse between Obama and the House GOP over debt had severely shaken the confidence of investors in U.S. financial markets. The new House may be even more resistant to a debt ceiling increase with Obama winning a second term.

Slideshow: On the campaign trail

Reuters, Getty Images

In the final push in the 2012 presidential election, candidates Mitt Romney and Barack Obama made their last appeals to voters.

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Confirmation of pivotal Cabinet members and regulatory chiefs
After securing a second term, Obama will, at a minimum, need to nominate a new Treasury Secretary to replace outgoing Tim Geithner and a new secretary of state to replace Hillary Clinton. Depending on the mood and membership of the Senate, the nomination hearings could prove contentious. Obama will also need to win Senate confirmation for those nominees selected to fill 82 judicial vacancies.

Implementing the Affordable Care Act and appointing the members of the Independent Payment Advisory Board
The administrative mechanism to carry out “Obamacare” needs to be designed, refined and run. Congressional Republicans are especially hostile to the Independent Payment Advisory Board, an outside body of experts, picked by the president, which is supposed to propose cuts in Medicare spending, with those cuts getting special fast-track consideration in Congress. So far Obama has appointed none of IPAB’s 15 members. Those nominees will be subject to Senate confirmation. 

Chaos in Syria, WMD – and don't forget Iran
The phrase “weapons of mass destruction” may have gone out of fashion after U.S. forces failed to find any in Iraq after they invaded in 2003, but there’s no dispute that the Syrian regime does possess a large arsenal of chemical weapons, including nerve gas. Some of those weapons and ingredients might go missing as the civil war grinds on. Meanwhile Syria’s ally Iran has carried on work to build nuclear weapons and is not cooperating with the UN’s International Atomic Energy Agency which is trying to find out more about the Iranians’ secret research.

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Updated at 8:40a.m.ET: PORT ST. LUCIE, Fla. – In a major foreign policy speech Monday Mitt Romney will attempt to stake out a more activist public position than President Barack Obama on supporting the rebels in Syria's civil war. Romney plans to say that he believes in working with partner nations to arm rebels fighting the government of Syrian President Bashir al-Assad.

Slideshow: Behind Syrian rebel lines

Machine guns operated by motorcycle brakes? Get a glimpse at the rebels fighting against Assad's forces in Syria's mountainous Jabal al-Zawiya area.

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He would equip the rebels – “who share our values” -- with heavy weapons to take out "tanks, helicopters and fighter jets," according to the remarks. The Obama administration has refrained from doing so out of concern that the weapons would end up in terrorist hands, according to The New York Times.

Romney will also argue that the U.S. must support the rebels to develop influence and good relations with the Syria’s future leaders.

Slideshow: On the campaign trail

Reuters, Getty Images

In the final push in the 2012 presidential election, candidates Mitt Romney and Barack Obama make their last appeals to voters.

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Syria is just one area Romney will touch on in a speech in which the Republican nominee will attempt to portray himself as a leader firmly in the peace-through-strength tradition of Harry Truman and Ronald Reagan, while casting President Obama as an ineffective leader on a dangerous and constantly-evolving world stage.

Related: Who are the Syrian rebels?

Romney will deliver a 30-minute address, titled "The Mantle of Leadership," later Monday at the Virginia Military Institute, his 10th address on the topic of foreign policy since summer 2011.

Recommended: Obama urges supporters not to lose enthusiasm

The former Massachusetts governor's speech, like the others before it, will focus on a vision of peace through strength. It will include new details on how Romney would address current global hotspots and repeat regular stump speech staples – such as the importance of averting planned defense cuts, expanding and reinvesting in the U.S. military and working closely with allies abroad, especially Israel.

In prepared remarks released Sunday to reporters, Romney laid out global issues where his campaign hopes to draw "great contrast" with Obama – notably on Libya, Syria and Egypt.

Slideshow: Mitt Romney's life in politics

Jonathan Ernst / Getty Images

From governor's son to presidential contender, a look at the life of Republican Mitt Romney.

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The speech links the attack on the American consulate in Benghazi last month to al-Qaida, a position Romney has rarely engaged in on the campaign trail. Romney calls the attack "likely the work of the same forces that attacked our homeland on September 11th, 2001," and "the deliberate work of terrorists." The attack was not, he says, a spontaneous response to a movie trailer maligning the Muslim Prophet Mohammad, as the Obama administration initially said.

As he did at the Clinton Global Initiative last month, Romney will argue that U.S. aid to Egypt should be linked with promises from Egyptian leaders to uphold the 1979 peace treaty with Israel and to protect minorities, including the country’s Coptic Christians.

Romney, who offended some Palestinians with remarks he made in Israel suggesting the economic disparities between the Palestinian territories and Israel were based in part on cultural differences, will also promise to "recommit" to helping form a democratic Palestinian state alongside Israel.

"In this old conflict, as in every challenge we face in the Middle East, only a new President will bring the chance to begin anew," say Romney’s prepared remarks.

On the infamous "47 percent" tape of a Florida fundraising event in May, Romney predicted the Israeli/Palestinian conflict would "remain [an] unsolved problem."

"We have a potentially volatile situation, but we sort of live with it," Romney said at the May fundraiser, comparing the peace process to the decades-long standoff between China and Taiwan. "And we kick the ball down the field and hope that ultimately somehow, something will happen to resolve it."

During a Sunday conference call with reporters, Romney foreign policy advisers said Monday’s foreign policy speech was meant to align Romney with the foreign policy tradition of Harry Truman, Ronald Reagan and George Marshall.

"If you look at Harry Truman and John Kennedy and the use of power by Bill Clinton in his second term that is a much different approach than Jimmy Carter and Barack Obama so I do think it’s a bipartisan tradition, it’s a recognition that strength is not provocative, its weakness that’s provocative," former Ambassador Rich Williamson, a Romney foreign policy adviser, said on the call. "There’s a fundamental difference between Barack Obama and Mitt Romney and that’s part of the choice that American voters will be asked to make."

Democrats fired back preemptively at that characterization.

"Mainstream foreign policy isn't what Mitt Romney is putting forward: having plans to start wars but not end them; wanting to keep 30,000 U.S. troops in Iraq indefinitely; exploding our defense spending to levels the Pentagon has not asked for, with no way to pay for it; insulting our allies and partners around the world on the campaign trail; and calling Russia our number-one geopolitical foe," Obama campaign spokesperson Lis Smith said in a statement Sunday. "If that's where Mitt Romney thinks the mainstream is, he needs to find a better compass."

Aboard Air Force One Sunday, Jen Psaki, the Obama campaign's traveling press secretary, was more cutting when asked her views on the speech.

"We're not going to be lectured by someone who has been an unmitigated disaster on foreign policy every time he's dipped his toe in the foreign policy waters," Psaki told reporters. "The only person who has offended Europe more is probably Chevy Chase."

President Barack Obama said he would have to rethink his current opposition to U.S. military engagement in Syria if the regime there were to use or move its chemical and biological weapons.

The president told NBC's Chuck Todd that he couldn't be "absolutely confident" that the stockpiles of weapons possessed by Bashar al-Assad's regime were completely secure.

"What I'm saying is we're monitoring that situation very carefully," Obama said in a surprise appearance in the White House briefing room.

But if the Assad regime were to use its weapons stockpiles, or alternatively, move it around, Obama suggested military action could be on the table.

"We have been very clear to the Assad regime, but also to other players on the ground, that a red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized," the president said. "That would change my calculus. That would change my equation."

Earlier this month, when asked about contingency planning for the Syrian conflict, Secretary Hillary Clinton drew the "red line" at only the use of chemical weapons.

"Both the minister [Turkey Foreign Minister Ahmet Davutoglu] and I saw eye to eye on the many tasks that are ahead of us, and the kinds of contingencies that we have to plan for, including the one you mentioned in the horrible event that chemical weapons were used. And everyone has made it clear to the Syrian regime that is a red line for the world," Clinton said at the time.

But today, he made sure to emphasize that all major players in the region have been informed of where his line falls.

"We have communicated in no uncertain terms with every player in the region that that's a red line for us and that there would be enormous consequences if we start seeing movement on the chemical weapons front or the use of chemical weapons," he said. "That would change my calculations significantly."

Obama also made a point of saying that the issue of chemical weapons doesn’t just concern Syria and the United States, but also allies in the region including Israel.

While the international community would still like to see a political solution to the violence in Syria, Obama said, “at this point the likelihood of a soft landing seems pretty distant."

The U.S. will most likely provide even more monetary humanitarian assistance to help those fleeing the Syrian conflict on top of the $82 million the government has already given. According to USAID, the United Nations “estimates that approximately 2 million people in Syria are in need of humanitarian assistance, approximately 1 million people are internally displaced, and more than 140,000 people have fled to the neighboring countries of Jordan, Turkey, Lebanon, and Iraq.”