Our all-volunteer armed forces have consistently lived up to their promises. They should expect nothing less from the nation that sends them into harm's way.

Now members of both political parties have a chance to volunteer as well -- to support bills introduced by U.S. Rep. John Kline, a Republican, and Sen. Amy Klobuchar, a Democrat, that would ensure that returning U.S. military personnel get the paid-leave benefits they were promised.

That includes members of Minnesota's "Red Bulls," the 1st Brigade Combat Team of the 34th Infantry now deployed in Kuwait.

The issue arose last fall when the Pentagon changed the rules regarding the Post Deployment/Mobilization Respite Absence program.

The PDMRA program is designed to give service members more time to reintegrate with their families and communities when they return from deployment. Given that many members have had multiple deployments, this time is particularly important.

But under the new guidelines, the length of leaves provided to some of the 2,700 Minnesota National Guard members could be cut in half -- some might lose up to 27 days of earned leave if the new rules remain in effect.

Both bills would restore the promised benefit level to those troops deployed before Oct. 1, 2011.

This isn't the first time the rules have changed mid-deployment. Congressional intervention was needed in 2007 in order to get $10 million in compensation restored to troops after an extended deployment to Iraq.

It shouldn't take congressional action to get the Pentagon to live up to its promises. And in this case, it doesn't.

Both Kline and Klobuchar said that Defense Secretary Leon Panetta can make the change unilaterally. Panetta was noncommittal in a House hearing, and he has not responded to written requests on the rule change.

According to Kline and Klobuchar, the Pentagon has not been clear on what led to the change. Money is most likely the motivation: America's unsustainable budget deficit means that the Pentagon budget, like those of nearly every other governmental sector, will soon shrink.

The Defense Department is facing at least $487 billion in cuts over the next decade, and more cuts could come under budget triggers set for next year.

Kline said the Congressional Budget Office had not yet "scored" the bill, so no specific cost estimate on what it would take to restore the benefits is available. But "in terms of putting it on a scale of personnel costs, it's minuscule. Yet in terms of its relationship to the morale of these troops and others, I think it's pretty big."

Once our nation promises military members something, it's a moral imperative that we deliver. The Red Bulls, who became the longest-serving brigade combat team in the Iraq war, are especially deserving.

Panetta should quickly cut his losses on this unwise and unfair rule change and restore the PDMRA benefits to the previous promised level.

Short of that, the bills from Kline and Klobuchar should easily move through Congress. Keeping this commitment is the least the U.S. government can do to support the troops.