House Minority Leader Nancy Pelosi has launched an aggressive campaign designed to maximize Democratic support for President Obama’s proposal for U.S. military strikes on war-torn Syria.

The California Democrat emphasized Tuesday that she and other Democratic leaders would not twist arms with a formal whip of a Syria vote. But in a press conference at the White House, and then in a letter sent to all her troops, Pelosi is laying out a very public case for intervention with an unequivocal humanitarian message aimed to rally wary Democrats behind their president.

{mosads}“It is in our national interest to respond to the Syrian government’s unspeakable use of chemical weapons,” Pelosi wrote in her “Dear Colleague” letter. “Indeed, it has been, and remains, a core pillar of our national security — under Democratic and Republican administrations — to prevent, limit, and halt the spread and use of nuclear, chemical, and biological weapons. 

“This is a matter of national, regional, and global security,” she added.

The remarks come as a number of liberal Democrats are warning that U.S. intervention would do little to help the civilian victims of Syria’s yearslong civil war or unseat the regime of President Bashar Assad. Instead, the critics say another military operation in the Middle East would simply fritter away taxpayer dollars better spent on humanitarian aid to Syria and projects at home.

“We’re in a situation where we’re not going to do anything that’s going to do any good,” Rep. Alan Grayson (D-Fla.) said Tuesday in an interview with CNN. “No one in the administration says this will cause regime change, this attack that’s being contemplated. No one in the administration is even saying it will prevent Assad from using chemical weapons again. … There’s no contemplation that any attack that we launch will end the civil war.

“I feel bad about it,” Grayson added, “but sometimes you have to recognize your own limitations. Otherwise, it’s hubris.”

Pelosi conceded that she won’t get every Democrat on board — “Some won’t ever be comfortable with it,” she said — but she’s hoping emerging evidence about Assad’s alleged chemical attacks will convince on-the-fence Democrats that intervention is necessary.

“On these kinds of issues, it’s not a question of whipping, it’s a question of discussion — to make sure that people have the information that they need to make an informed decision, to make sure that they have the full value of the intelligence that says this is how this happened,” she said, following a meeting with Obama and congressional leaders. 

“And then members have to decide, are they willing … to ignore the fact that this humanitarian disaster took place or not?”

Pelosi also argued that the president has the authority to intervene in Syria even if Congress votes against the authorization he’s requested. That puts the Democratic leader at odds with more than 50 liberal Democrats in her camp, who penned a letter to Obama last week warning that any strikes without congressional approval would be unconstitutional. 

“While we understand that as Commander in Chief you have a constitutional obligation to protect our national interests from direct attack, Congress has the constitutional obligation and power to approve military force,” the lawmakers wrote.

The debate puts Pelosi in somewhat of a tough spot, as the Democratic leader has often touted Democratic opposition to the Iraq War as a central distinction between the parties. Now, with a Democratic president urging Congress to authorize an unpopular attack in the same region, Obama is counting on Pelosi to deliver the votes.

Pelosi got a good deal of political cover on Tuesday, when Speaker John Boehner (R-Ohio) and Majority Leader Eric Cantor (R-Va.) both endorsed Obama’s desire to use force against Assad. 

“America has a compelling national security interest to prevent and respond to the use of weapons of mass destruction, especially by a terrorist state such as Syria, and to prevent further instability in a region of vital interest to the United States,” Cantor said in a statement.

Still, even some Democratic leaders are withholding their endorsement of a new military campaign. Rep. James Clyburn (S.C.), for instance, said Tuesday that he wants more information before deciding how to vote.

“Issues of war & peace require thoughtful consideration,” Clyburn tweeted.  “I reserve judgment on Syria until a resolution and more details are forthcoming.” 

Rep. Marcia Fudge (D-Ohio), head of the Congressional Black Caucus, has also yet to take a position, her office said Tuesday. 

Much will likely depend on the scope of the authorization language. Indeed, many Democrats have been critical that the resolution proposed by the White House over the weekend is too broad. 

In response, Rep. Chris Van Hollen (D-Md.) is crafting alternative language to narrow the powers granted to the White House, his office said Tuesday.