Fears of another prolonged confrontation along the lines of Iraq and Afghanistan have given many lawmakers pause. The conundrum has also given way to the spectacle of ostensible defense hawks becoming restive about another military action against Syria, while erstwhile doves — many of them Obama supporters — voice full-throated support for a strike against Damascus.
However, Menendez — one of several key Democrats who opposed the 2003 invasion of Iraq — cautioned about "the consequences of inaction" if the US failed to confront Damascus. He argued that American reticence could resonate across a region already embroiled in conflict, especially as Egypt, Libya and other Middle Eastern countries grappling with civil instability.
"I voted against the war in Iraq, so I don't come to the use of force easily, but this has clear significance to our national security," Menendez said. "We have the wherewithal to strike against Assad's regime in ways that not only undermine his ability to deliver chemical weapons…[but] undermine the regime itself."
Should the U.S. fail to act, it would send a message to America's opponents that "they can act aggressively, violate international law and do so without consequence. I think inaction has a greater consequence than action." That includes Iran and North Korea, the senator added.
Over the long U.S. holiday weekend, Secretary of State John Kerry and other Obama administration officials took to the airwaves to make the case for a military strike against Syria.
--By CNBC's Javier E. David.