(CNSNews.com) - "While we all condemn the atrocities in Syria, the United States was not attacked," Sen. Rand Paul (R-Ky.) said Thursday night in a statement on his website and in a series of tweets.

"The President needs congressional authorization for military action as required by the Constitution, and I call on him to come to Congress for a proper debate. Our prior interventions in this region have done nothing to make us safer, and Syria will be no different."

Sen. Tim Kaine (D-Va.) and Rep. Barbara Lee (D-Calif.) are on Sen. Paul's side in the emerging debate:

"President waging military action against Syria without a vote of Congress? Unconstitutional," Kaine tweeted Thursday night.

In a second tweet, Kaine said, "Assad is a brutal dictator who must be held account for atrocities. But the President's failure to seek congressional approval is unlawful."

Kaine for years has urged Congress to come up with a new authorization for the use of military force in Iraq/Syria.

As CNSNews.com previously reported, he is among a minority in Congress who believe that the 2001 Authorization for the Use of Military Force against the 9/11 perpetrators "does not provide a legal justification" for the fight against Islamic State terrorists in Iraq and Syria.

Rep. Barbara Lee (D-Calif.) is urging Congress to come back into session:

"This is an act of war. Congress needs to come back into session & hold a debate. Anything less is an abdication of our responsibility," Lee tweeted Thursday night.

In a second tweet, Lee said, "I was the lone vote against 2001 AUMF. Syria strikes are far beyond the scope of this war authorization. @SpeakerRyan needs to bring a vote."

Senate Minority Leader Chuck Schumer issued a statement, supporting the air strike but telling Trump to "come up with a strategy":

"Making sure Assad knows that when he commits such despicable atrocities he will pay a price is the right thing to do," Schumer tweeted. "It is incumbent on the Trump administration to come up with a strategy and consult with Congress before implementing it. I salute the professionalism and skill of our Armed Forces who took action today."

The liberal activist group MoveOn.org, which reflexively opposes all that President Trump says and does, is circulating an emergency petition, telling Congress to vote "no" on a new authorization for the use of military force, to "halt Trump's march toward war."

"Things could spiral quickly in the coming hours, and it's up to MoveOn members to lead a chorus of progressives in every corner of this nation saying NO to bombing the people of Syria," MoveOn.org said in an email announcing its emergency petition.

MoveOn is calling the limited air strikes on a Syrian air field "an illegal and unauthorized escalation taht could have devastating consequences, killing innocent Syrians and costing the lives of U.S. service members."

The group's message reads as follows: