The top uniformed Army and Marines generals told a Senate panel Friday that letting gays serve openly in the military during wartime would be divisive and difficult, opposition that could undercut President Barack Obama's push to repeal the "don't ask, don't tell" ban.
The generals' doubts about the White House effort gave political ammunition to Arizona Sen. John McCain and other Senate Republicans trying to block Democratic efforts to overturn the 1993 law prohibiting gays in the military from acknowledging their sexual orientation.
The generals' testimony came one day after Defense Secretary Robert Gates and Adm. Mike Mullen, the military's top uniformed officer who chairs the Joint Chiefs of Staff, pressed for Congress to repeal the ban, arguing that wartime is the ideal time for such a step. Gates and Mullen also said lawmakers should act before the courts do.
Democrats have promised a vote this month to repeal the "don't ask, don't tell" law, but its chances of passing this year were considered slim and may have been wounded further by the generals' skepticism.
Both Casey and Marine Corps Commandant Gen. James Amos acknowledged that openly gay service was probably inevitable and they played down suggestions that recruiting and retention would suffer dramatically if it was allowed.
But, they warned that repealing "don't ask, don't tell" would be tougher than a recent Pentagon study suggests and advised that repeal shouldn't happen so long as troops continue to fight in Afghanistan.
"My suspicions are that the law will be repealed," Amos said. "And all I'm asking is the opportunity to do that at a time and choosing when my Marines are not singularly tightly focused on what they're doing in a very deadly environment."
Amos, whose military branch has expressed the most discomfort with the change, said that "assimilating openly homosexual Marines into the tightly woven fabric of our combat units has strong potential for disruption at the small unit level, as it will no doubt divert leadership attention away from an almost singular focus of preparing units for combat."
Their opposition was backed by Air Force Chief of Staff Gen. Norton Schwartz, who suggested putting off changing the policy until 2012.
McCain said the testimony by the service chiefs should be given special consideration. He said he wanted to hear from other uniformed officials, including senior enlisted personnel and combatant commanders, and that the Pentagon study backing repeal shouldn't be the final word.
"It's a little bit like studying the Bible," McCain said. "You can draw most any conclusion from what part of it you examine."
Chief of Naval Operations Adm. Gary Roughead was the only Pentagon service chief to advocate for repeal.
Roughead said it was likely that some highly trained combat sailors, including Navy SEALs, might refuse to re-enlist in protest of the personnel change. But, he said, he did not think any long-term damage would occur if certain steps were taken, such as increased training.
Released earlier this week, the study found that a minority of troops — about 30 percent — predicted potential problems if "don't ask, don't tell" were repealed.
But most of the troops with concerns were serving in combat roles. Nearly 60 percent of troops in the Marine Corps and in Army combat units, such as infantry and special operations, said they thought allowing gays to be open about their sexual orientation would hurt their units' ability to fight on the battlefield.
"I cannot reconcile, nor turn my back, on the negative perceptions held by our Marines who are most engaged in the hard work of day-to-day operations in Afghanistan," Amos said.
Compared to Amos, the Army's Casey was somewhat more optimistic that repeal could happen without causing major turmoil among his troops. Casey said the policy shift, if implemented properly, wouldn't keep the Army from doing its job, and he predicted repeal would pose only a moderate risk to his force.
But, he added, changing the law now would "add another level of stress to any already stretched force" and be more difficult on the Army, particularly its combat units, than the recent Pentagon study suggests.
Gates and Mullen have said they believe resistance can be addressed through training and education. They also cite experience with gay troops as a mitigating factor. According to the study, 84 percent of Marines in combat roles who find they're working with a gay comrade said they did not see any negative impact on unit morale or cohesion.
"In terms of actual disruption experienced, as opposed to predicted disruption, the distinction between combat arms communities and the force as a whole is negligible," said Marine Gen. James Cartwright, the No. 2 officer on the Joint Chiefs of Staff.
McCain has dismissed the military study as flawed because it did not ask troops whether they thought the law should be repealed in the first place, focusing instead on the impact repeal might have. McCain also contends that Pentagon leadership was glossing over serious objections expressed by troops in Marine and Army combat roles at a time of two wars.
Cartwright countered in his testimony that implementing change at a time of war might actually be preferable because troops are focused on their mission.
"The challenges associated with making a change of any kind that seem enormous during periods of inactivity become less distracting when you are defending your nation and comrades," he said.