From Vietnam veterans to fresh young recruits, from seasoned officers to anxious mothers worried about their sons' safety on the streets of Baghdad and Fallujah, the military community is growing ever more vocal in its opposition to the White House.

"I once believed that I served for a cause: 'To uphold and defend the Constitution of the United States'. Now I no longer believe that," Tim Predmore, a member of the 101st Airborne Division serving near Mosul, wrote in a blistering opinion piece this week for his home newspaper, the Peoria Journal Star in Illinois. "I can no longer justify my service for what I believe to be half-truths and bold lies."

The dissenters - many of whom have risked deep disapproval from the military establishment to voice their opinions - have set up websites with names such as Bring Them Home Now. They have cried foul at administration plans to cut veterans' benefits and scale back combat pay for troops still in Iraq. They were furious at President Bush for reacting to military deaths in Iraq with the phrase "bring 'em on".

And they have given politically embarrassing prominence to such issues as the inefficiency of civilian contractors hired to provide shelter, water and food - many of them contributors to the Bush campaign coffers - and a mystery outbreak of respiratory illnesses that many soldiers, despite official denials, believe is related to the use of depleted uranium munitions.

"It is time to speak out because our troops are still dying and our government is still lying," Candace Robison, a 27-year-old mother of two from Krum, Texas, and a politically active serviceman's wife, told a recent protest outside President Bush's Texas ranch. "Morale is at an all-time low and our heroes feel like they've been forgotten."

How deep the anti-Bush sentiment runs is not yet clear, but there is no doubt about its breadth. Charlie Richardson, co-founder of a group called Military Families Speak Out, said: "Our supporters range from pacifists to people from long military traditions who have supported every war this country has ever fought - until this one.

"Many people supported this war at the beginning because they believed the threat from weapons of mass destruction and accepted the link between Saddam Hussein and al-Qa'ida ... Now they realize their beliefs were built on quicksand. They are very angry with the administration and feel they've been duped."

"We have all faced death in Iraq without reason or justification," he added. "How many more must die? How many more tears must be shed before Americans awake and demand the return of the men and women whose job it is to protect them rather than their leader's interest?"

Less visible, but no less passionate, has been the ongoing voicing of grievances over the internet. A prominent military affairs specialist, David Hackworth, keeps a website filled with angry reflections on conditions in Iraq for both the military and the local civilian population, and the government that put the troops there. "Imagine this bastard getting away with such crap if we had a draftee army," runs one typically scabrous anti-Bush line from Mr Hackworth.

"How many of these people that are 'stranded' (for lack of a better term) in Iraq are going to re-enlist? How many that haven't deployed are going to re-enlist ... how many families are going to be destroyed?" he asked.