At Speicher base in Iraq, US Army Spec. Jeremy Hall got permission from a chaplain in August to post fliers announcing a meeting for atheists and other nonbelievers. When the group gathered, Specialist Hall alleges, his Army major supervisor disrupted the meeting and threatened to retaliate against him, including blocking his reenlistment in the Army.

Months earlier, Hall charges, he had been publicly berated by a staff sergeant for not agreeing to join in a Thanksgiving Day prayer.

On Sept. 17, the soldier and the Military Religious Freedom Foundation (MRFF) filed suit against Army Maj. Freddy Welborn and US Secretary of Defense Robert Gates, charging violations of Hall's constitutional rights, including being forced to submit to a religious test to qualify as a soldier.

The MRFF plans more lawsuits in coming weeks, says Michael "Mikey" Weinstein, who founded the military watchdog group in 2005. The aim is "to show there is a pattern and practice of constitutionally impermissible promotions of religious beliefs within the Department of Defense."

For Mr. Weinstein – a former Air Force judge advocate and assistant counsel in the Reagan White House – more is involved than isolated cases of discrimination. He charges that several incidents in recent years – and more than 5,000 complaints his group has received from active-duty and retired military personnel – point to a growing willingness inside the military to support a particular brand of Christianity and to permit improper evangelizing in the ranks. More than 95 percent of those complaints come from other Christians, he says.

Others agree on the need for the watchdog group, but question the conspiratorial view and some of its tactics. They say dealing with religious issues is a complex matter, and the military is trying to address them appropriately.

At the Defense Department, spokeswoman Cynthia Smith says the DOD doesn't comment on litigation, but "places a high value on the rights of members of the Armed Forces to observe the tenets of their respective religions."

Since the Revolutionary War, the armed services have tried to ensure that soldiers can practice their faiths, and that chaplains serve not only those of their own sect but all who may need pastoral care. The services have also sought to adhere to the First Amendment prohibition of any government "establishment of religion."

In the 1990s, for instance, the Air Force's Little Blue Book of core values highlighted religious tolerance, emphasizing that military professionals "must not take it upon themselves to change or coercively influence the religious views of subordinates."

Weinstein insists, however, that there are improper actions at high levels that not only infringe on soldiers' rights but, at a very dangerous time, also send the wrong message to people in the Middle East that those in the US military see themselves engaged in Christian warfare.

For example, he says, Lt. Gen. William Boykin, who gave speeches at churches while in uniform that disparaged Islam and defined the war on terror in fundamentalist, "end times" terms, was not fired but promoted. (Speaking of a Muslim warlord he had pursued, Lt. Gen. Boykin said, "I knew my God was a real God and his was an idol." And our enemies "will only be defeated if we come against them in the name of Jesus.")

"There's an eschatologically obsessed version of Christianity that ... is trying to make American foreign and domestic policy conterminous with their biblical worldview," Weinstein charges. And "there's improper pressure within the military command structure to make members join them."

The most serious allegations from the field cannot be corroborated for this article. A few will be raised in the lawsuits, but some incidents have been documented.

Perhaps the most visible situation – and the one that set Weinstein off on his mission – involved the evangelizing of cadets on the part of some faculty and staff at the Air Force Academy (AFA) in Colorado Springs, Colo., which came to light in 2004. Congress held hearings, DOD conducted an investigation, and the head of the academy acknowledged significant problems. Weinstein's cadet son experienced the pressures as a Jew.

Col. David Antoon (ret.), another alumnus of the AFA and now a 747 commercial pilot, says his heart was broken when he took his son, Ryan, to an orientation at the academy in the spring of 2004. An overt evangelistic approach during part of the orientation so upset them, he says, that they decided his son would reject the treasured appointment and instead go to Ohio State University.

"My son had dreamed of doing what I had done, but it was no longer the institution I went to," Colonel Antoon says, his voice cracking with emotion.

The Air Force set about reaffirming basic principles in religion guidelines, as a basis for widespread training, but a pushback by Evangelicals later led to Congress setting them aside until hearings could be held. The hearings have not taken place.

In 2006, MRFF learned of a video produced by Christian Embassy, a group that conducts Bible studies at the Pentagon and seeks to evangelize within the armed services. Aimed at fundraising for the group, the video was improperly taped in the Pentagon and involved endorsements by Army and Air Force generals in uniform.

MRFF's public alert spurred a DOD investigation. In a report critical of the senior officers, the Inspector General said they gave the appearance of speaking for the military. One general defended his role by saying "Christian Embassy had become a quasi-federal entity."

The report noted that Maj. Gen. Paul Sutton participated while he served as chief of the US Office of Defense Cooperation in Turkey, a largely Muslim nation whose military takes pride in protecting the country's secular status. After a Turkish newspaper wrote about the video as promoting a "fundamentalist sect," General Sutton was called in and questioned by members of the Turkish General Staff.

"They had to give him a lesson in the separation of church and state," Weinstein says. "Imagine the propaganda bonanza! And how this upset Muslims."

The DOD report on the video recommended "appropriate corrective action" be taken against the officers. According to Army spokesman Paul Boyce, "The Army has not yet completed any planned actions associated with the Christian Embassy review."

MRFF claims a victory in the case of the evangelical group Operation Stand Up. Earlier this year, OSU was preparing to send "freedom packages" to soldiers in Iraq as part of an Army program. Along with socks and snacks, the packages included proselytizing materials in English and Arabic, and the apocalyptic video game, "Left Behind: Eternal Forces." In it, Christians carry on warfare against people of other faiths.

After the plans were made public, the Pentagon announced in August that the materials would not be mailed. OSU did not respond to a request for comment.

Weinstein – an intense, voluble attorney who prizes blunt, no-holds-barred language – has struck more than one nerve with his bird-dogging. He says numerous threats have been made on his life. Last week, the front window of his house was shot out for the second time. After the lawsuit was filed, talk of "fragging" (killing) Specialist Hall surfaced on some military blogs. The Army is investigating.

Others sympathetic to Weinstein's concerns say some tactics undermine his efforts, and they question aims.

"He's uncovered some very disturbing stuff that shouldn't be going on in the armed forces," says Marc Stern, a religious liberty expert at American Jewish Congress. "But it's important that you not go too far." Mr. Stern disagrees, for instance, with Weinstein's stance on the Air Force guidelines, such as preventing military supervisors from ever speaking of religion to people under their command.

"He did a disservice to his and our cause by taking a position beyond what the law requires, and in fact may intrude on people's rights," Stern adds.

Several conservative Christian ministries publicly proclaim an evangelistic aim "to transform the nations of the world through the militaries of the world," and they are active at US military installations in many countries. (See www.militaryministry.org or militarymissionsnetwork.org.)

MRFF sees that as a harbinger of a volunteer military falling under the sway of increasing numbers of Christian soldiers. Others see a military leadership, with the exception of a few generals here or there, well aware of its constitutional responsibilities, but challenged by the demands of training on these issues in a military of millions. A group such as MRFF can provide a crucial service, they say, if it is willing to work with the military.

Right now, Weinstein is counting on a set of lawsuits to bring serious issues to the fore. The question is whether those suits will go beyond individual cases of discrimination to prove an unconstitutional pattern within the armed forces.