As opposition to a U.S. strike in Syria seems to build in the House of Representatives, three key officials in the Obama administration took their case to the Capitol today, adamant that military intervention is in line with the country's national security interests.

Still, Republicans on the House committee on Foreign Affairs expressed grave reservations about entering into what they deem a Syrian civil war.

Secretary of State John Kerry, fielding the bulk of questions from war-wary lawmakers on the committee, implored Congress to vote in favor of a resolution authorizing military force so that Syrian President Bashar al-Assad will not be emboldened with "impunity."

"We're taking an action that is in our interest, in our national security interest in order to enforce a long-time standard [against the use of chemical weapons]," Kerry testified. "If that is not enforced, the world will be less safe, and our citizens, no matter where you live in this country, will be less safe because the likelihood is greater that somebody somewhere will get their hands on those materials as a result of our inaction."

Kerry, who was joined by Secretary of Defense Chuck Hagel and Chairman of the Joint Chiefs of Staff Gen. Martin Dempsey, did his best to convince members that the resolution does not put "boots on the ground." But many members did not hold back their qualms that a military strike could spark a wider conflict and draw U.S. troops into a ground war.

"This will not stop the butchering and the killing that takes place over there. So what is the purpose? What is the endgame here? Where is the imminent danger to the United States?" Rep. Tom Marino, R-Pa., asked. "Soldiers coming home deformed and limbless and even in a body bag is not acceptable to me and, therefore, I cannot and will not vote for this intervention in Syria."

Hagel responded, "This specifically notes that no boots would be on the ground, this resolution that is being drafted."

"I've heard that before," Marino shot back.

Other lawmakers said they were troubled about supporting what is perceived widely in Congress as an opposition force that is filled with radical Islamists who have joined the fight to overthrow Assad.

"Every time I get briefed on this, it gets worse and worse because the majority now of these rebel forces - and I say majority now - are radical Islamists pouring in from all over the world to come to Syria for the fight," Rep. Mike McCaul, R-Texas, said. "My concern is any strike against this regime, as bad as it is, will empower these radical Islamists, these extremists.

"We've seen this movie before," he continued. "We've seen Afghanistan. We've seen what happened in Egypt. We saw what happened in Libya. We saw what the Arab Spring has brought us, and it's not good. They filled a vacuum. They have filled a vacuum."

While the Aug. 21 attack has grabbed the attention of the world, Rep. Joe Wilson, R-S.C., questioned why President Obama had chosen not to enforce his "red line" after previous chemical weapons attacks by the Assad regime were confirmed in the past year.

"With the president's red line, why was there no call for military response in April?" Wilson asked. "Was it delayed to divert attention today from the Benghazi, IRS, NSA scandals; the failure of Obamacare enforcement; the tragedy of the White House-drafted sequestration or the upcoming debt limit vote?"

Kerry said Obama made a decision to change his policy after the attack late last month, but in previous cases of chemical warfare, the president "didn't believe that the evidence was so overwhelming."

"It was significant, it was clear it had happened, but on a scale that he felt merited the increase of assistance and the announcements that he made with respect to the type of aid that he would provide the opposition," Kerry said. "The president thinks that as a matter of conscience and as a matter of policy, the best route to proceed is through the military action now."

Wilson concluded, "Chemical weapons are chemical weapons."

Rep. Ted Poe, a Republican from Texas, asked Dempsey whether he had formulated a contingency plan

"Can you see that escalating, though, with U.S. military involvement in the region?" he asked. "Have you made contingency plans for us being in an escalated military operation in the region?"

"Yes," Dempsey acknowledged. "I can never drive the risk of escalation to zero, but … the limited purpose, the partnerships we have in the region, [and] the contributions that we'll seek from other I think begins to limit that risk."

Kerry emphasized at the conclusion of the hearing, "I don't believe we're going to war. I just don't believe that. Going to war is mobilizing a force, asking people to join up, fighting a long campaign, committing your troops on the ground, fighting to win and so forth. That's not what we're doing here."