(CNN) -

After President Barack Obama said he didn't yet have a strategy for ISIS in Syria, even a Democrat on Sunday criticized the President's approach to fighting the extremist terror group.

There's been the expected GOP criticism: Rep. Adam Kinzinger, R-Illinois, said the President's statement was "unfortunate," a predictable assessment from someone who disagrees with the Obama's handling of foreign policy.

But more notable is Sen. Dianne Feinstein, the top Democrat on the Senate Intelligence Committee, who split with the leader of her party.

"I think I've learned one thing about this President and that is he's very cautious. Maybe in this instance, too cautious," the California Democrat said on NBC's "Meet the Press."

Feinstein's description comes as the Obama administration is implementing a split strategy in dealing with the group now calling itself the Islamic State.

In Iraq, where America recently concluded a long war there, the United States has continued airstrikes against ISIS, including strikes near Amerli Saturday. In Syria, meanwhile, the President has been reluctant to pursue military action as a complicated web of factions, including ISIS, is fighting to defeat President Bashar al-Assad, also a U.S. opponent.

The threat

While members of both parties indicated that Syria is the most dangerous country in the world right now as it is considered ISIS' home base, Republicans differed from Democrats in that they insisted that the threat ISIS poses to the U.S. is immediate. "I believe strongly that ISIS does plan on attacking the United States," Rep. Peter King said on "Fox News Sunday."

Sen. John McCain went even further on CBS News' "Face the Nation": "I think it starts with an understanding that this is a direct threat to the United States of America, that it may be one of the biggest we have ever faced."

The top Republicans' statements come just days after British Prime Minister David Cameron elevated the terror threat to "severe," the second-highest rating for that country.

But the top Democrat on the House Intelligence Committee, Rep. Dutch Ruppersberger of Maryland, played down the immediacy of a direct attack in the United States on CNN's "State of the Union," saying strong intelligence "at this point" of an imminent attack on the U.S. does not exist.

Another Democrat, Rep. Adam Smith of Washington, acknowledged the threat ISIS poses is real, but it's "a bit of an overstatement" to compare the threat of ISIS to al Qaeda.

"There is no evidence at this point that they are actually doing the sort of command-and-control plotting, planning specific attacks against Western targets, like al Qaeda was, gosh, for better -- for almost a decade before 9/11," he said on "Face the Nation."

'A cancer'

Kinzinger used a cancer analogy describing ISIS, expanding upon an opinion piece written by Secretary of State John Kerry in The New York Times Friday when he said "the cancer of ISIS will not be allowed to spread to other countries."

"If you have cancer in your liver, and it's spreading to other parts of your body, you don't just treat the other parts, you treat the liver," the Iraq War veteran said on CNN's "State the Union." "The liver is Syria."

While the President has been taking heat for saying he doesn't have a strategy for ISIS, a Democrat on the House Intelligence Committee discussed the challenges in formulating a strategy, in part, because obtaining intelligence about ISIS from war-torn Syria has been difficult.

"We have got to get the intelligence," Ruppersberger said.

Smith echoed his colleague's sentiment.

"We can't simply bomb first and ask questions later. We have to have the right targets and the right support in order to be effective in stopping ISIS," he said on CBS News' "Face the Nation."

On Friday, Rep. Joe Courtney, D-Connecticut, and others sent a letter to House Armed Services Committee Chairman Buck McKeon, asking that committee members return to Washington ahead of schedule in order to oversee Obama's response to ISIS and the possible expansion of airstrikes.

"We are very concerned that due to the speed with which events are happening, waiting until September 8th for Congress to reconvene effectively sidelines our constitutional role. We respectfully request that the Armed Services Committee reconvene as early as possible to provide the needed oversight over this new development," they wrote.

In response, a spokesman for McKeon said the chairman appreciates the sense of urgency and that oversight can take a variety of forms.

"Currently the chairman and other members of the committee are traveling in the Middle East, consulting regional leaders on this important issue. A classified briefing for committee members -- covering ISIS as well as the events in the Ukraine -- is scheduled for the Tuesday members return," said Claude Chafin.

Military action now -- or soon