He shook his head.

The protest was concentrated in Baghdad, and people were brought in from other cities to participate rather than holding smaller simultaneous demonstrations across the country.

Although the event was carefully organized and scripted by Mr. al-Sadr, a populist anti-American Shiite cleric, and given heft by Iraqi armed groups close to Iran, it also reflected a genuine desire shared by Iraqis to have a government and economy that serves the Iraqi people and not outside interests, many participants said.

Delivering on that may prove to be virtually impossible. But the United States’ recent actions in Iraq drew the wrath of many and distaste even among some Iraqis who support the United States presence.

It is particularly galling to many that the United States still has troops in Iraq and many people point out that while Iran also has influence, it does so without imposing its troops on the country. The armed groups that are part of the Popular Mobilization, even though they are backed by Iran, are not perceived in the same way.

“We don’t need any foreign troops to be in Iraq, we need Iraq for Iraqis,” said Hoda Hashimi, an employee in the Ministry of Trade in Baghdad. “We don’t want Americans to leave, we want the troops to leave — we want America to support our country but with contracts, not troops.”

This demonstration — unlike those in Tahrir Square in central Baghdad, which have gone on for months and involve a ragtag group of antigovernment protesters with homemade signs and a range of backgrounds — is heavily orchestrated rather than a spontaneous outpouring of feeling.

Participants were recruited, transported by buses provided by the organizers and given signs, flags and sometimes food. The vast majority of the participants are Shiite Muslims, who are the main constituency of the cleric Mr. al-Sadr and the armed groups close to Iran.