U.S. Army Force Restructuring, “Modularity,” and Iraq

U.S. Army Force Restructuring, “Modularity,” and Iraq

The U.S. Army is reorganizing to create smaller, more mobile units without sacrificing firepower. Some experts, however, wonder whether that aim addresses the lessons of Iraq.

Last updated October 26, 2007 8:00 am (EST)

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The U.S. Army, built around divisions of ten thousand to fifteen thousand soldiers since World War I, began a radical reform of its organizational structure in 2004 that designates the much smaller “brigade”—with three thousand to five thousand soldiers—as the linchpin of the army’s structure. The reforms, which took on new urgency as the strain of maintaining a large combat force in Iraq grew, reflect the fact that a unit of the size of today’s “Brigade Combat Teams” (BCTs) can bring to bear the destructive power equal to that of a much larger division of decades past. At the end of the reform process—by early 2008—the army will field forty-three BCTs, which operate independently, in comparison to the thirty-three brigades available in 2004, which under the old structure were designed to operate primarily as part of a division.

The new brigades are intended to be “modular,” meaning their smaller battalion- and company-level components can be mixed and matched by the brigade’s commander to suit the particular mission. (This Backgrounder provides a fuller examination of modern military unit structures.) In theory, the new brigades require fewer support troops, making them more self-sufficient and, theoretically, increasing the percentage of forces available to deploy in combat roles. In practice, some experts wonder whether the unforeseen length of the deployments in Iraq and Afghanistan will blunt the value of some of the reforms.

More Deployable Combat Power

The architects of the modular army estimate the reforms will produce a force with a 30 percent increase in deployable combat personnel and a 50 percent increase in the “ready pool” of deployable National Guard and Army Reserve forces, though some experts challenge those numbers. Still, the army believes the reforms will produce a more predictable, less stressful deployment pace for soldiers by increasing the time between deployments abroad, and, in turn, increasing retention rates. The active army, reserve, and guard are in the midst of making these changes, detailed in this broad 2007 Army Modernization Plan.

The army considered several factors when designing these new combat ratios. First, modular units notionally are far easier to supply with the weapons, spare parts, and other equipment needed to keep them in the field longer than the older divisions, which specialized in things like mountain warfare or armor. The smaller and less complicated “logistical tail” of the new units means less bureaucracy and fewer logisticians servicing it.

Second, in the shift to brigades from divisions the army has emphasized self-sufficiency. The reform’s architects hope this will mean less demand for administrative and “headquarters” units and more leeway for brigade commanders to operate independently. Finally, increased retention rates theoretically mean more skilled active-duty or ready-reserve forces, reducing the amount of time needed to prepare inexperienced forces for new missions.

Iraq Lessons Learned?

Yet some experts worry these changes—sparked by the sluggish pace of army deployment from bases in Germany and the United States to assist in the 1999 NATO-led war against Serb forces in Kosovo—fail to internalize the lessons of the Iraq war. In Iraq, a relatively small U.S. force won a quick victory over the much larger, conventional Iraqi Army. But these forces were caught short when an insurgency and post-war occupation demanded new capabilities such as the ability to stabilize occupied areas and conduct operations against insurgents. A recent Congressional Research Service report (PDF) on army modular reforms notes that some experts “question the design of the Army Modular Force in terms of its ability to successfully conduct counterinsurgency and stabilization operations." In a critique of the modular reforms, Col. Bryan G. Watson, an army brigade commander, argues “the major capability gap in today’s force—and vital for future campaigns—is the ability to conduct stabilization as part of expeditionary land warfare.” Watson also asserts that “the Army’s major transformation effort—the Modular Force—does little to improve the Army’s stabilization capability.” Another analysis, by Lt. Col. Stephen L. Melton in Military Review, suggests the reforms may wind up doing exactly the opposite of the original intention by “unwittingly sacrificing foxhole strength in combat arms to build underused, redundant headquarters structures.”

The army already has dismissed some of these criticisms, saying the Third Infantry Division, its first to be converted to the new modular structure, performed as well or better than other units during its recently ended deployment to Iraq. But some officers complained that during its time in Iraq, the Third Infantry found it necessary to cannibalize other units (InsideDefense.com) to maintain the kind of reconnaissance capabilities division-based units are accustomed to.

Deeper Structural Issues

No one has addressed fully the question of whether the modular configurations actually bear on the most serious problem the army had in the Iraq war: its struggle to handle a long-term, post-conflict “stability” operation. In Iraq, the combined resources of the army and Marine Corps, which together list an “end-strength” on paper of some 690,000 troops, have strained mightily to sustain the “surge” troop level of 169,000.

Why? It’s a reasonable question. Even accounting for the 180,000-odd troops deployed overseas outside Iraq (primarily in Afghanistan, Germany, South Korea, Japan, Italy, Djibouti, Cuba, and elsewhere), over half a million army and Marine Corps troops are presumably still available to “sustain the surge.”

The mathematics, of course, are not that simple. At any one time, combat-ready brigades account for about two-thirds of the army’s total strength, the rest including administrative, logistical, and other noncombat uniformed personnel. Those troops regarded as combat capable exist in one of three phases in the army’s deployment cycle: already deployed, preparing and retraining for deployment, or regenerating and recuperating from a recent deployment. Though exact numbers are difficult to find for any one moment, this means, roughly, that only one-third of the army’s strength can be deployed at any given time. The ratio today is far higher because of National Guard and Army Reserve mobilizations, and because Secretary of Defense Robert M. Gates extended deployments in Iraq from twelve months to fifteen months earlier this year. But that also means forces on the other end of the cycle are getting less time between deployments, with implications both for readiness and, ultimately, retention. 

Large Deployments Other Than Iraq

Other missions, too, sap the army’s ability to deploy in Iraq. Some eighteen thousand continue to fight in Afghanistan. Eight thousand National Guard troops are attached to homeland security duties in the United States. Some seven hundred troops serve in the Sinai Desert as part of a force established after the Camp David Accords between Israel and Egypt. Another 1,500 just deployed to the multinational force patrolling Kosovo. Some six hundred run the prison at Guantanamo Bay, Cuba, and operations involving one hundred or fewer troops continue from the Philippines to Africa to Europe.  

The army does not argue that modularity is a single-source solution to this numbers crunch. Many in and outside the army, for instance, have argued for downsizing the large presence that persists in Germany and Japan (which 62,000 and forty thousand U.S. troops call home, respectively). Others want to hand peacekeeping commitments, like the ones in Kosovo and the Sinai Desert, over to other militaries.

But some experts feel modularity ultimately fails to increase the percentage of deployable combat troops in the total force precisely because these smaller brigades require infrastructure that the old system housed at the division level. “They’ve solved a problem that really didn’t exist,” says Stephen Biddle, CFR senior fellow and a military expert. “The idea that you need to be able to send smaller units than divisions into trouble zones sounds good, but the fact is, the United States almost never does that. Even the smaller combat deployments generally involve twenty thousand troops.”

Meanwhile, Biddle says, each brigade now needs a headquarters, with its own doctors, lawyers, accountants, and logisticians. So the net gain in efficiencies may be far less than advertised.

The Surge and Enlargement

For much of the Bush administration, the Pentagon under Secretary of Defense Donald H. Rumsfeld ruled out the idea of enlarging the army and the Marine Corps, largely because of doctrinal and budgetary reasons. A larger ground component of the U.S. military, several senior defense officials argued, would run counter to the very idea of “transforming” the heavy tank-laden Cold War armed forces into a more mobile, high-tech, twenty-first century force. Similarly, the increase in personnel costs, already the largest single line item in the Pentagon’s budget, would reduce funds available for pursuing new high-tech weaponry, not only for the army and the Marine Corps, but also for naval and air forces. 

Last January, however, under congressional pressure, Gates announced a plan (AP) to increase the active-duty army and Marine Corps end strength from the current authorized level of 547,400 army soldiers and 202,000 marines. In total, the plan adds 65,000 soldiers and 27,000 marines over the next five years. The Congressional Budget Office estimates the cost of this expansion will amount to about $108 billion by 2013. Gordon Adams, former associate director of national security at the Office of Management and Budget, told CongressDaily that these burdens could turn into a budget buster for the Pentagon. “It will do nothing to alleviate force stress in Iraq, unless you assume we are there in large numbers for another three [to] five years,” he said. The army’s Fiscal Year 2008 budget projects major increases in personnel costs beginning in Fiscal Year 2009.

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