Tuesday�s highly anticipated congressional testimony by General David Petraeus, the top military commander in Iraq, and Ryan Crocker, the U.S. Ambassador to Iraq, appeared to be an exercise in futility.

Despite tough questions and somewhat heated exchanges between Democratic lawmakers and Petraeus and Crocker, the Democratic leadership has signaled it has no immediate plans to flex their legislative muscle to change the direction of the conflict while President Bush is still in the White House.

In fact, Democrats will soon convene Senate hearings to debate a supplemental spending bill that calls for pouring another $100 billion into Iraq until late September. More than $500 billion has been spent to fund military operations in Iraq, much of it through emergency legislation passed by Congress since 2003. Democratic lawmakers have said the legislation is certain to pass and is unlikely to include any benchmarks, specifically, those that sets a specific date for withdrawing U.S. troops.

Realizing they are unlikely to fulfill their 2006 midterm election promise to voters that they will swiftly change the course of the war, the Democratic leadership in both houses, in a last ditch effort to change the direction of the occupation, sent a letter to President Bush last Friday asking that he reconsider his military approach.

�The current Iraq strategy has no discernible end in sight and requires the United States to spend additional hundreds of billions of dollars despite urgent national needs in education, health care, and infrastructure improvement, and when high oil prices have provided the Iraqi government with billions in additional revenue that could pay for their own redevelopment and security," says the letter, signed by Speaker of the House Nancy Pelosi of California, House Majority Leader Steny Hoyer of Maryland, Senate Majority Leader Harry Reid of Nevada, and Senate Democratic Whip Dick Durbin of Illinois. �This strategy is neither sustainable nor in our broader national security or economic interest . . . We are deeply concerned that you and the congressional Republican leadership are intent on staying the current course throughout your administration and then handing the Iraq war off to future presidents.�

Not surprisingly, Bush did not issue a response.

Still, if lawmakers were serious about radically changing the direction of military operations in Iraq they have several legislative options at their disposal, according to a recent report issued by the Congressional Research Service (CRS), the investigative arm of Congress.

The 52-page report, �Congressional Authority to Limit U.S. Military Operations in Iraq,� says Congress can �enact legislation that restricts the scope of military operations through appropriations.�

�Congress�s ability to deny funds for the continuation of military hostilities is not contingent upon the enactment of a positive law, though such a denial may take the form of a positive enactment,� the report says. �Although the President has the power to veto legislative proposals, he cannot compel Congress to pass legislation, including bills to appropriate funds necessary for the continuation of a military conflict.�

The report says that �a simple majority of a single House could prevent the appropriation of funds necessary for the continuation of a military conflict,� but suggests that legislation probably would be required to prevent the president from exercising statutory authority to transfer certain funds appropriated to other operations for use in support of the military conflict that Congress was attempting to limit.

With the presidential race in full swing and a fear that they will continue to be characterized as weak on national security, the likelihood that Democrats would even consider following through on any of the report's suggestions seems far-fetched at best. Still, the report is a sobering reminder that Congress could succeed in challenging Bush�s assertions that, as commander-in-chief, he can act unilaterally and that any attempt by lawmakers to interfere with that dual role would represent an unconstitutional violation of the separation of powers principles.

�There has been some suggestion in the past that the President�s responsibility to provide for troops in the field justifies further deployments without prior authorization from Congress, with some arguing that the President has an independent implied spending power to carry out these responsibilities,� says the February 28 report. �These arguments do not easily square with Congress�s established prerogative to limit the scope of wars through its war powers, and do not conform with Congress�s absolute authority to appropriate funds.�

�At least two arguments support the constitutionality of Congress�s authority to limit the President�s ability to increase or maintain troop levels in Iraq,� the report added. �First, Congress�s constitutional power over the nation�s armed forces provides ample authority to legislate with respect to how they may be employed. Secondly, Congress has virtually plenary constitutional power over appropriations. Article I provides that �No Money shall be drawn from the Treasury, but in Consequence of Appropriations made by Law.� It is well established, as a consequence of these provisions, that �no money can be paid out of the Treasury unless it has been appropriated by an act of Congress� and that Congress can specify the terms and conditions under which an appropriation may be used.�

CRS says in past wars Congress has historically succeeded in forcing an administration to change its military strategy by using the �power of the purse.�

�In cases of significant differences with the President over foreign policy, especially deployments of U.S. military forces abroad, Congress has generally found that use of its constitutionally-based 'power of the purse' to be the most effective way to compel a President to take actions regarding use of U.S. military force overseas that he otherwise might not agree to," the report said. CRS issued several reports last year stating that to change the dialogue about Iraq, Congress may be forced to pursue the politically unpopular route of reducing or significantly limiting war funds.

"Two well-known proposals -- the McGovern-Hatfield amendment and the Cooper-Church amendments -- were also part of this jockeying between the administration and Congress. The first prohibited expenditure of previously appropriated funds after a specified date 'in or over Indochina,' except for the purpose of withdrawing troops or for protection of US troops during the withdrawal, while the second prohibited the expenditure of any funds after July 1, 1970, to retain troops in Cambodia unless specifically authorized by law hereafter. Overall, funding restrictions have generally proven more effective than the War Powers Act, which has been challenged by the executive branch on constitutional grounds," the report says.

But Democrats are unwilling to pursue that course of action -- not while President Bush is occupying the White House.

"I expect most of our troops to still be there" until at least the end of the year, said Sen. Carl Levin, the Democratic chairman of the Armed Services Committee, during a conference call with reporters last Friday. "Until there's either a big enough majority in the Senate or a change in the president's [strategy], I don't see a significant improvement in Iraq."