WASHINGTON -- Despite broad political support for President Bush's plan to expand US ground forces by 92,000 troops, a growing number of military strategists and defense specialists are questioning the need for so many more conventional combat forces.
They say the additional troops will not be available in time to relieve the strain on the Army and Marines from the wars in Iraq and Afghanistan, and there has been virtually no discussion in Washington on the purpose for the largest military expansion since the end of the Cold War.
The specialists, who represent a diverse set of viewpoints, fundamentally question whether maintaining a larger standing military -- 547,000 active-duty Army soldiers and 202,000 Marines once the new troops are added -- is the most effective way to fight smaller but lethally innovative groups of Islamic terrorists and other less traditional security threats.
"The global war on terrorism and Iraq are being used as lame rationales" for enlarging the military, said retired Lieutenant Colonel Frank Hoffman , a researcher at the Marine Corps Center for Emerging Threats and Opportunities in Quantico, Va. "Unless you think we will have more than six brigades in Iraq in 2012, I don't see how this is relevant."
Nonetheless, the president's call to increase the Army and Marine Corps by nearly 15 percent over the next five years -- at an initial cost of nearly $100 billion and at least $15 billion per year thereafter -- has received nearly universal support in a Congress dominated by Democrats.
When Bush made the appeal in his State of the Union speech, he drew applause from both sides of the aisle. Congressional leaders said the decision was long overdue and pledged to act swiftly, including fast-track approval of the initial $12 billion the Pentagon needs to start recruiting, housing, and training the first batch of new volunteers next year.
Top Pentagon officials have said the fresh recruits -- 65,000 for the Army and 27,000 for the Marine Corps -- would allow the Pentagon to slow its troop rotations to battle zones in Iraq and Afghanistan.
Secretary of Defense Robert M. Gates unveiled the proposal in January. He assured the troops in the war zones, some of whom have served two or more combat tours since the wars began, that "help is on the way."
The Army would like to keep active-duty soldiers at their home base for at least two years for every one year they deploy, easing the home-front burden on families and loved ones. Yet strain on the ranks has forced most combat troops to do another tour of duty after only a year at home.
That trend also has prevented many Army and Marine Corps units from maintaining their training schedules for different missions. Lieutenant Colonel Michael Johnson of the Army's Transformation Office said that fewer, shorter rotations to the battle zone will help units decompress and retool before heading out again.
Yet a small but influential group of defense policy specialists, speaking through military journals and internal Pentagon briefings, point out that the new ground forces would not be battle ready for at least several years -- perhaps past the US military's involvement in Iraq.
"The military is stressed in Iraq, there is no doubt about it," said Gordon Adams , a former White House national security aide under President Clinton and now a professor of international affairs at George Washington University. "But everybody accepts that 92,000 [new soldiers and Marines] is not going to fix that. It will be three to five years before you have an additional force that is useful."
Others say it is unlikely that the United States would take on another Iraq-style military invasion and occupation, and a larger conventional Army isn't good at stopping terrorists and insurgents, who favor suicide bombings and guerrilla-style fighting. Moreover, any potential conflicts against major world powers in the near future probably would not involve a large overland invasion.
"The notion that we would occupy a country and try to do what we said we would do in Iraq again is hard to imagine at this point," said Michael Vlahos, a self-described conservative and member of the national security assessment team at Johns Hopkins University's Applied Physics Lab, which conducts classified work for the Defense Department.
Vlahos, who has conducted studies for the Pentagon's Defense Science Board, said ground forces are best suited for short-term objectives, such as the toppling of Saddam Hussein in Iraq or the evacuation of American citizens from war-torn nations.
But "we cannot go in and take over a society and achieve what we want. That is what Iraq has shown," Vlahos said in an interview. "That sounds harsh but that is the bottom line."
Douglas McGregor , a defense consultant and a retired Army colonel, said Bush's planned expansion of US ground forces "is a bad idea," especially "if the increase is for conducting unwanted occupations" such as Iraq. McGregor said Britain's turbulent history as a colonial power is an object lesson against that strategy.
"This is the 21st century, not the 19th," McGregor said. "There is no country in the world today that the United States or Britain should occupy."
Still, some skeptics of the troop increase worry that Democrats and Republicans in Congress have been persuaded that the Pentagon needs more troops at its disposal.
"I think there is widespread belief that because of the Iraq experience we have to have more forces to do more Iraqs properly," said Charles Pena, a senior fellow at the Independent Institute in Oakland, Calif. "It implies that policy makers intend to embark on more military operations that might require a sizable US military presence in other people's countries."
Said the Marine Corps' Hoffman: "We have an excess of military capacity already involved in the global war on terrorism. Infantry brigades and tank battalions are not needed to offset Osama bin Laden or Al Qaeda."
Hoffman and others fear that giving the Pentagon more muscle is far more about bureaucracy and politics than national security. Putting nearly 100,000 more volunteers in uniform can help politicians ease the public angst over the Iraq war while brushing up their strong-on-defense bona fides -- what Adams calls "bureaucratic opportunism."
"The easy thing to do is say the Army needs more people," said David Johnson , a military specialist at the government-funded Rand Corporation. "But I don't think anybody has had the discussion, 'For what?' "
At least one influential Democrat, Senator Carl Levin of Michigan, tried to start that discussion last month.
"It is important that we understand exactly what these additional personnel will be needed for, in the long term," Levin remarked in an Armed Services Committee hearing on Feb. 6. "Does the [Bush] administration think the 'long war' with terrorism is going to be won with large ground forces operating in foreign nations?"
Bryan Bender can be reached at email@example.com