BAGHDAD - President Bush called a crackdown on militias critical to success in Iraq, but Prime Minister Nouri al-Maliki has been noticeably silent, perhaps because the plan would mean confronting the same violent radicals who have been helping Shiites expand their political dominance.

In announcing a new Iraq policy Wednesday night, Bush said earlier efforts, three of them since May, to tame the bloodshed in Baghdad had been snarled by "political and sectarian interference (that) prevented Iraqi and American forces from going into neighborhoods that are home to those fueling the ... violence.

"This time, Iraqi and American forces will have a green light to enter those neighborhoods," Bush said. "Prime Minister Maliki has pledged that political or sectarian interference will not be tolerated."

But whatever he said in private, Maliki, a Shiite, has avoided making that pledge in public. Instead, he has stuck with formulaic utterances, saying that anyone illegally carrying weapons will be dealt with harshly.

Announcing his vision of the new security plan last Saturday, Maliki said he would fight against "safe haven for any outlaws, regardless of (their) sectarian or political affiliation."

He said the same thing in October but then ordered U.S. forces to pull back from attacks on Sadr City, headquarters of the Mahdi Army. The violent Shiite militia is headed by his key political backer, radical cleric Muqtada al-Sadr.

Maliki instead has encouraged the Americans to go after rival Sunni insurgents, especially in the territory west of Baghdad where few Shiites live.

Experts say that even if Maliki assures Bush of support, his behavior illustrates that he is not as Bush described, a man whose primary concern is bringing peace and prosperity to his country.

"The Bush administration has one view of Iraqi reality in which Maliki is ... an honest broker," said W. Patrick Lang, a former head of Middle East intelligence at the Defense Intelligence Agency. "In my view, Maliki is one of any number of Shiite Arab activists who are seeking to consolidate Shiite control."

The radical Shiites are predicting Bush's plan is doomed.

"We reject Bush's new strategy, and we think it will fail," said Abdul-Razzaq al-Nidawi, a senior official in Sadr's office in the Shiite holy city of Najaf.

"We call upon the American people to oppose sending more of their sons to Iraq so that they will not be flown back in coffins," he said.

Maliki, who first outlined a new Iraqi-led security plan to Bush when they met in Amman, Jordan, in November, has never sought an increased U.S. military footprint in Iraq. He has argued for the Americans increasingly to pull out of the cities and leave security to the Iraqi army, which is 80 percent Shiite.

The Americans would respond only when needed.

An Iraqi general said earlier this week that the army intended to put nine brigades on the streets of Baghdad, or a total of about 27,000 men.

The force would be commanded by a Shiite, Lt. Gen. Aboud Qanbar, who was taken prisoner of war by U.S. forces during the 1991 Persian Gulf War and will report directly to Maliki.

The military officer, who spoke anonymously because the information was not yet public, said that for the most part the Iraqi force would not be directed against the Shiite militias.

The majority of fighting against the Mahdi Army in Sadr City would be left to the Americans in tandem with the Iraqi Special Operations Command, which is made up of many non-Arab Kurds as well as Sunni and Shiite Arabs.

Muqtedar Khan, a senior fellow at the Saban Center for Middle East Policy at the Brookings Institution, said he suspects the Iraqi leader is simply trying to placate the Americans, whom, it seems, he can't live with or without.

"This is the kind of game most global politicians are born with," said Khan, who is also a professor of Islam and global studies at the University of Delaware. "It's called managing Washington."

Maliki is in a tight spot, he said, caught between his radical Shiite supporters and his American backers, who help finance and protect his fractious government.

Khan sees a way out, but he is doubtful Maliki can pull it off.

"If Maliki can send a message that he is for the Iraqi people and that's he tough," he may survive, Khan said, explaining that the prime minister needs to find a way to convincingly tell ordinary Iraqis that "I'm tough on Sadr; I'm tough on Bush."

But Lang thinks that if Maliki allows U.S. troops to clear Shiite areas of militias, his "position will become more and more impossible, and his government will fall."