WASHINGTON — President Bush said yesterday that his decision to send more troops to Baghdad is yielding “gradual but important” progress in Iraq. He portrayed himself as steadfast while Democrats squabble over strategy.

War-weary voters put Democrats in charge of Congress, but lawmakers have not decided how or whether to restrict Mr. Bush on Iraq through legislation. Mr. Bush seized on that divide and cautioned Democrats not to interfere with military missions.

“Other members of Congress seem to believe that we can have it all: that we can fight Al Qaeda, pursue national reconciliation, initiate aggressive diplomacy, and deter Iran’s ambitions in Iraq — all while withdrawing from Baghdad and reducing our force levels,” Mr. Bush said in a speech to the American Legion.

“That sounds good in theory, but doing so at this moment would undermine everything our troops have worked for. There are no shortcuts in Iraq,” the president said.

The House speaker, Rep. Nancy Pelosi, a Democrat of California, said Democrats are determined to lead a new direction on Iraq policy. That includes getting troops home and shifting the American mission from combat to training, troop protection and counterterrorism.

“The war in Iraq is not making our country safer, our military stronger or the region more stable,” Ms. Pelosi said yesterday. “In fact, the war in Iraq is the greatest ethical challenge facing our nation.”

The war is deeply unpopular. The White House also has been rocked by reports of shoddy care for wounded soldiers at a premier Army hospital in Washington, angering lawmakers in both parties.

Mr. Bush said Democrats have a right to express their opinions. Then he methodically criticized several of their ideas: adding unrelated items to a war spending bill; narrowing the mission in Iraq, or placing conditions on money for the war.

The House has approved a symbolic measure disapproving of Mr. Bush’s troop buildup. The proposal has stalled in the Senate. The White House is preparing for what it sees as the real political fight —the upcoming vote on a $100 billion war spending bill.

Mr. Bush said Congress should approve the war money without strings or delay. Military commanders, he said, should have “the flexibility to carry out their missions without undue interference from politicians in Washington.”

Meanwhile, Mr. Bush said a security crackdown in Baghdad is showing “encouraging signs.” The White House sees stability in the Iraqi capital as the centerpiece of a political, military, and diplomatic plan to winning the war.

“Iraqi and U.S. forces are making gradual but important progress almost every day,” Mr. Bush said. “We will remain steadfast until our objectives are achieved.”