US Secretary of State John Kerry told senators on Tuesday it is time to " stand up and act " against the Syrian government as he made a forceful case for a military strike on the Middle Eastern country."This is not the time for armchair isolationism," Kerry said in testimony before the Senate Foreign Relations Committee. The hearing marked the first by Congress to consider President Barack Obama's request for authorization to use military force in Syria after the US intelligence community claimed that the Syrian government had launched a chemical weapons attack on militant strongholds last month. Kerry claimed the evidence is clear the government of Syrian President Bashar al-Assad was responsible for the August 21 attack and that Americans cannot "be spectators to slaughter." Inaction in response to the alleged chemical attack would open a "Pandora's box" of "dangerous consequences," damaging America’s credibility, he added. Kerry also raised some questions on the potential use of ground troops in Syria. “I don’t want to take off the table an option that might or might not be available to a president of the United States to secure our country,” he said when asked whether the Obama administration would accept a ban on boots on the ground. Defense Secretary Chuck Hagel and Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff also joined Kerry to press lawmakers to authorize the use of force in Syria. Hagel said that, "The word of the United States must mean something." "A refusal to act would undermine the credibility of America's other security commitments.” The Pentagon chief also said that several key allies in the region strongly support US military strikes on Syria. The push for military intervention came after President Obama announced on Saturday that he would seek congressional authorization for military strikes against Syria. Obama himself continued to press for support in remarks Tuesday morning before he met with congressional leaders at the White House. "I've made a decision that America should take action, but I also believe that we will be much more effective, we will be stronger, if we take action together as one nation," Obama said, appealing to members of Congress to back his military plan. "The key point that I want to emphasize to the American people [is] the military plan that has been developed by the joint chiefs - and that I believe is appropriate - is proportional; it is limited; it does not involve boots on the ground," Obama said. Meanwhile, the Congress seems to be divided on giving the Obama administration authorization to attack Syria. Sen. John McCain (R-Ariz.), a leader of the Senate’s hawk faction, has said that he would not back limited strikes and that any military involvement by the United States should achieve the purpose of regime change in Syria. On the other side, lawmakers such as Rep. Adam Schiff (D-Burbank), a House Intelligence Committee member, and Senator Rand Paul, Republican of Kentucky, have warned that attacking Syria could draw the US into another Mideast war. Multiple opinion polls have found that the American public is also widely opposed to a US military action against Syria.