Updated

The fall of Ramadi to Islamic State forces -- despite Obama administration efforts to downplay it as a short-term setback -- has kicked up a sandstorm of problems for the White House:

-- The possibility that Iran-backed Shiite militias will take a lead role in the fight to retake the city;

-- Fresh political fallout over President Obama's decision to withdraw virtually all troops in 2011 -- against the advice of his top military commanders -- only to watch hard-fought U.S. gains undone by ISIS; and,

-- Congressional pressure from both sides of the aisle to rethink the current anti-ISIS military strategy.

Taken together, the problems pose a political and strategic migraine for an administration trying to manage the Iraq-Syria madness -- while also forging a nuclear deal with Iran, seeking a resolution in war-torn Yemen and keeping tabs on the rest of the tumultuous post-Arab Spring nations, including Egypt and Libya.

More On This...

    On Tuesday, congressional pressure mounted over the course of the U.S. military's anti-ISIS strategy.

    House Speaker John Boehner said Obama should "start over" with his congressional request for use of military force against ISIS -- a request that has stalled on Capitol Hill. Boehner said Obama needs to come up with a clear strategy, adding: "We know that hope is not a strategy. The president's plan isn't working."

    While skepticism from GOP leaders is hardly new, the criticism took on a bipartisan streak Tuesday as the top House intelligence committee Democrat piled on.

    "Alarm bells should be going off," said Rep. Adam Schiff, D-Calif., according to The Daily Beast. Schiff reportedly questioned the current strategy that relies largely on airstrikes, and also voiced concern that the on-the-ground approach relies too much on Iran-backed militias. (At the same time, Schiff said he was "deeply disappointed" by Boehner's call to restart talks on the authorization for use of force.)

    He's not alone in his concerns over strategy and Iran's role. On Sunday, House Homeland Security Committee Chairman Michael McCaul, R-Texas, told Fox News the Shiite militias will only inflame the Sunni tribes in Iraq. As they did in the battle for Tikrit, the Shiite militias once again are being looked to by the Iraqi government to help in Ramadi.

    "I think this is a prescription for disaster," McCaul said.

    Sens. Lindsey Graham, R-S.C., and John McCain, R-Ariz., voiced similar concerns.

    "I think they may be able to take Ramadi back, but you know who they're going to take it with? The Shia militias, which are Iranian-run, sponsored, trained and equipped," McCain told Fox News. "And they are going to go into a Sunni area and they're not going liberate, my friend. The Sunnis will never reconcile with the Shia militias, which are sponsored by the Iranians.

    "... And that, of course, will mean a lot more bloodletting."

    Aside from concerns about Iran taking a lead role in the battle to retake Ramadi, the weekend's defeat of Iraqi security forces marks a troubling reversal of U.S. gains in the region -- Ramadi is part of the so-called Sunni Triangle, which saw heavy fighting in the intermediate years of the Iraq war.

    McCain noted that hundreds of Americans died trying to wrest Ramadi from Al Qaeda in Iraq, out of which spawned ISIS.

    "I can't imagine what some of the troops are thinking as they see where they had such terrible sacrifices," former Defense Secretary Robert Gates told Fox News.

    He said, at this point, sending in a "huge new U.S. force" would be a mistake, but said the U.S. could "more effectively" use the assets it has in the region.

    "Getting [ISIS] out of these cities is going to be incredibly tough," Gates acknowledged. But he said if ISIS is allowed to keep the territory permanently, "What you have is a cancer in the middle of the Middle East."

    With the Obama administration again facing criticism for not keeping a residual force on the ground after 2011, Gates said the reason the country was better off in 2010 and 2011 was "we had a presence on the ground."

    A Pentagon spokesman vowed Monday that "we will retake Ramadi."

    A senior defense official also denied there were plans to change the approach to fighting ISIS in light of the weekend's takeover.

    "There are no plans to change our strategy," he said.

    White House Press Secretary Josh Earnest said Tuesday that "overall," the U.S. strategy to fight ISIS has been a success.

    In a glimmer of good news, Iraqi forces reportedly were able to repel an ISIS attack overnight in a location west of Baghdad.

    Fox News' Lucas Tomlinson contributed to this report.