Soldiers and Marines have had the most deployments, seen the toughest fighting and suffered the greatest number of U.S. casualties in recent wars. And as with most post-war periods, ground forces also will see their career opportunities tighten faster than for other service branches.
The Army plans to shed 60,000 troops, or 11 percent of its active force, to reach 490,000 by fiscal 2017. The Marine Corps will cut 20,000 -- 5000 a year over the next four years -- to reach an end-strength of 182,100.
Both services say they are determined through the drawdown to sustain force quality and to keep a proper mix of job skills and leadership experience to meet future requirements.
"Everything we do through the next five years is going to be about making the Army a quality force," said Al Eggerton, deputy chief of the officer division for the directorate of military personnel management.
"We've gotten an awful lot of experience in the last 10 years of war, and we're going to make selections to keep the very best of that that we can. And we're going to make sure we level our force across the optimum grades and skills and that we don't have any hollow points."
This time "we won't just be opening the door and allowing everyone to walk," he said. "We want to use precision, care and compassion."
Army leaders haven't reached final decisions yet on grade structure or skill mix for the post-drawdown force. So Eggerton can't say yet how force cuts will impact specific groups of officers or enlisted.
"That's a point of contention for field officers who would love to know exactly how we're going to do this. But at this point we've got the framework but not the decisions," Eggerton said.
When final decisions are made, perhaps soon after the election Eggerton said, "we will begin to look at each year group of the drawdown period and, by grades and skills, analyze our populations to determine where we need to pare and where there are shortages or gaps we have to fill."
The Army cut recruiting too deeply in the 1990s after the Cold War, creating hollow areas that later impacted the career force. Recruiting this time is falling more modestly.
From 2004 to 2010, the Army was expanding and officer promotion selection rates "were allowed to go fairly high because we needed to keep all the fully qualified people we had," Eggerton said. In the past two years, rates moved "back toward what was the norm prior to our large expansion."
So competition for promotion is rising. Some officers in overmanned skills, if not selected for promotion on a first pass, are being invited to leave service early through waivers of remaining service obligations.
Other officers are being offered "affiliation bonuses" to leave active duty for reserve components. To sharpen this incentive, the Army has asked Congress to double the maximum affiliation bonus to $20,000.
Army also has asked for authority to separate some officers involuntarily, anticipating that voluntary enticements and the usual promotion-board process of separating officers who twice fail selection to the next highest rank, won't get the Army to its drawdown targets fast enough.
"Some year groups and grades won't get a chance to be seen by the promotion process and separate through that, which would be more natural," Eggerton said. He can't say yet how many officers might be forced out if Congress grants that authority.
For the enlisted force, the goal is "precision retention" of careerists. Commanders will be able to deny even "enlisted members who are fully qualified the opportunity to re-up their contracts" based on service needs.
But the key force-shaping tool is the enlisted Qualitative Service Program, introduced earlier this year, to identify non-commissioned officers for involuntary early separation from active duty. A series of "centralized enlisted selection board processes," the QSP will allow tailoring of the force based on how well leaders have developed, and imbalances across skills.
The first QSP board in June denied continued service to 138 active duty and 40 Active Guard Reserve senior NCOs. Eight more boards are planned for 2013, all of them targeting grades and skills projected to be over strength or to lack viable career progression without QSP board action.
To be considered for QSP, soldiers who E-9 must have three years time in grade. Those in E-8 and below must have four years in grade.
Gen. James Amos, Marine Corps commandant, said the Corps plans no involuntary "reductions in force" that would cut service contracts short. That would not be "keeping faith" with Marines "who are bred on loyalty and faithfulness" and who have put their lives on the line again and again.
That said, competition to re-enlist, or for officers to extend service obligations, "will be a little more fierce" as the size of the Corps falls. This will incentivize Marines "to be the very best they can. So that is how I keep faith," Amos recently told a group of news reporters.
Like the Army, the Marine Corps has slowed recruiting. During the Iraq war, its accession target some years hit 35,000, Amos said, up from the normal 30,000. In fiscal 2012, the Corps signed only 28,500 recruits.
Meanwhile, first-term re-enlistments have become "much more competitive," Amos said. Combat experience alone is no guarantee a Marine will be retained because 70 percent of current Marines have seen combat.
And top-performing Marines who haven't seen combat shouldn't feel discouraged about their career prospects. First of all, the world "isn't getting any nicer out there," Amos said, so Afghanistan likely won't be the last chance this generation of Marines has to fight for their country.
But also a "superstar" Marine who hasn't seen combat will still compete favorably for promotion with a combat-experienced Marine who "is something less than a superstar player," Amos said. "Our system is designed, promotion-wise, actually to [find] the best Marine."
"Combat is a pretty good filter for the performance of a Marine under stress. But over time we have gone through periods of peace. And our bright young Marines have always floated to the surface in preparation for future combat," Amos said.