Updated

The Army will offer incentives to keep midlevel officers as it faces another decade or so in combat around the world, its chief of staff said Friday.

Gen. George Casey, who took over as the Army's chief just a month ago, said the United States will "be in a period of conflict for, I believe, another five or ten years." And the Army, which has been stretched and stressed by five difficult years at war, must be organized and equipped to deal with that challenge, he said.

The general said he is not suggesting that the Iraq or Afghanistan wars will last five more years. But Casey, who was the top commander in Iraq until February, acknowledged that building a stable, self-governing Iraq is a "long-term proposition."

"We have been attacked and are at war with an insidious group of transnational terrorists who are attacking our way of life, and are going to continue to attack our way of life until we beat them, because I don't see them giving up," he said.

To stem a growing trend of critical future leaders leaving the service, Casey said the Army will unveil a plan next week to give some captains $20,000 to stay on. He said the Army also will increase opportunities for officers to go to various graduate schools as another incentive to stay in the military. The captains also would get a choice in duty assignments.

Casey said leadership development is one of his priorities, along with increasing the size of the Army, improving conditions for soldiers and their families and continuing to transform the service so it can better fight future battles.

According to the Army, the attrition rate for officers is higher than it has been in previous years, with graduates of West Point, the Officer Candidate School and ROTC leaving at a faster pace once they've finished their initial tour in the military.

For example, about six in 10 West Point soldiers who graduated in 1997 reenlisted after their sixth year. But just 53 percent of those who graduated in 2000 — and likely have spent much of the last six years rotating in and out of the war zones — have signed up for another tour.

Casey, who served as the Iraq commander from July 2004 until February 2007, said he doesn't know how long the Army can keep up current troop levels in Iraq and Afghanistan.

But, he said, "it's a question I have foremost in my mind." He acknowledged that soldiers' families are upset about the Pentagon's recent decision to extend Iraq deployments to 15 months, from what had usually been 12 months.

But he said the move was the only way to avoid sending as many as five Army brigades back to Iraq after just seven or eight months at home, resting and getting the equipment and training needed to return to war. Under the new system, units are guaranteed 12 months at home.

The Pentagon released a one-page description Friday of the new deployment policy signed by Defense Secretary Robert Gates stating that units are guaranteed the one-year break. But it noted that a policy for individual soldiers has not yet been completed.

Some soldiers returning from Iraq may change to a new unit or switch jobs which could result in their being sent back to the war zone in less than 12 months. The Army is working on a policy that would address those instances as much as possible.

In other comments, Casey said he is still considering moving faster to increase the size of the Army but said he would have to shift money from future years in order to buy enough equipment for the expanded Army, as well as set up more recruiting centers.

He said he does not yet know how much money it would take.

Casey also said the Army is near a decision on how many mine-resistant armored vehicles to buy to replace the more vulnerable Humvees. The number is "somewhere between 2,500 and 17,000."

The Army wants more of the so-called MRAPs (Mine Resistant, Ambush Protected), but acknowledges there are missions for which the vehicle is not suitable or as agile as needed.