As Iraqi government forces struggle to hold their own against the self-declared Islamic State, the limitations of the current U.S. strategy have become clear. Our side is losing both individual battles and the larger war. Although the fight against the Islamic State will not be won by ground combat alone—Vietnam taught us too well the gap between tactical success and strategic victory—we must begin by winning on the battlefield. In turn, this will require a reexamination of how U.S. forces in the region operate, as well as what level of risk senior leaders are able to accept.

To address the Islamic State’s tactical successes, there are increasing calls to embed U.S. combat advisers with Iraqi government-aligned forces, removing restrictions that keep U.S. expertise far from the front lines. However, as Marcus Weisberger in Defense One points out, one does not simply embed U.S. troops in Iraq. Calls to allow U.S. troops to accompany Iraqi military units on offensive missions generally ignore support requirements. If we apply the risk-to-force calculus we have become accustomed to during the past fourteen years, the logistics and support tail required to support embedded advisers in Iraq would include medical evacuation, personnel recovery, combat search-and-rescue, quick reaction forces, and compounding logistics.

However, there is another approach. Recall the early days of Operation Enduring Freedom, when teams of Special Forces embedded as combat advisers with the the Afghan Northern Alliance. Those forces had no access to medical evacuation support, combat search and rescue assets, or a quick reaction force to provide backup. There were only small teams embedded with their come-as-you-are partners, backed up, of course, with devastating and well-coordinated airpower. There was no training program that took months or years to turn the Northern Alliance into a faint reflection of the U.S. military. We came to fight—fight light—and in doing so, enabled our partners to accomplish their own objectives.

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As we’ve seen in Afghanistan, tactical victory does not ensure strategic success, but it should be apparent from Iraq that strategic success is a pipe-dream if you can’t defeat the enemy on the ground. Some of our habits and assumptions developed over the last fourteen years also make it harder to win the tactical fight. The long, mostly static wars in Iraq and Afghanistan have accustomed the U.S. military to robust defensive force protection at forward operating bases, with layers of perimeter defense, an extensive guard force, and massive logistics support to supply and sustain these bases. In a drive to buy down risk, layers of support are stacked above and behind our frontline combat troops. Every American forward operating base becomes Fort Apache, a defensive oasis in “Indian country.”

This conventional approach to basing, sustainment, force protection, and fighting contrasts sharply with the light fighting ethos maintained by those Special Forces teams riding horseback with the Northern Alliance in the early days in Afghanistan. That wasn’t Fort Apache—it was just Apache.

In Iraq today—and in the hybrid and irregular small wars that will be thrust upon the United States in the future—operating concepts, as well as assumptions and expectations about force protection, must be reassessed. If we default to traditional, robust force protection for small teams of combat advisers, we will dramatically increase our manpower and logistics requirements. In this calculus, every addition of 500 troops requires twice that number or more to sustain and protect it. Not only is this calculus cost prohibitive, but it also ignores the current imbalance between offense and defense.

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Strike, through both complex asymmetric attack and precision weapons, has the upper hand over defense. The Islamic State has shattered Iraqi government bases with complex attacks using Vehicle-Borne IEDs (VBIEDs) and forces disguised as Iraqi army elements. The same has been shown in Ukraine, as tactical Russian unmanned aerial vehicles (UAVs) guiding precision Russian artillery and rockets have been employed to devastating effect against Ukrainian forces.

While our forces will perform much better than our Iraqi partners, complex asymmetric attacks remain a grave threat to our forward operating bases. Mobility, not fortification, should be considered the primary force protection tactic when the United States is fighting with small teams of advisers or strike teams. Once again, think Apache, not Fort Apache.

For example, U.S. attack and support helicopters should not operate from Iraqi air bases in urban areas that suffer from channelized lines of communication that make them prone to IED attack and result in the constriction of supply lines. These bases would require significant force protection measures and would become a magnet for attacks on the enemy’s terms and timetable. Instead, our helicopter and tactical UAV assets should operate from short-term, mobile, and constantly shifting forward arming and refueling points (FARPs) in the western deserts of Iraq, protected from attack by the expanse of the empty desert. Larger logistics and maintenance bases further away from the enemy could support these “lily pads.”

Carrying this concept further, U.S. (or coalition) mobile strike teams—operating from the desert expanse—should be used to disrupt the Islamic State’s extended and vulnerable lines of communication and take the fight to the enemy on our terms and at a time of our choosing in places where they are least prepared. These mobile strike teams would not be intended to take and hold territory, but rather to impose a cost on the Islamic State for holding territory. Iraqi government-aligned forces should take and hold territory; U.S. forces should harass, soften, and attrite these Islamic State militants in advance of Iraqi operations to regain lost ground.

Initiative is critical in warfare. We’ve come to expect that we need the Death Star hovering above us with endless logistics capabilities along with combat search-and-rescue assets, medical evacuation units, and quick reaction forces to do anything involving U.S. troops in combat. Static, fortified bases cede the initiative to the enemy. In modern warfare, being static means being vulnerable to both precision and asymmetric attack. Unconventional and light is the better approach—even if it carries a higher degree of tactical risk.

Ironically, of course, our attempts to “buy down” tactical risk through heavy combat support, fortified bases, and massive logistics trains increases operational risk through static forces and channelized, brittle logistics lines. Instead of reducing risk through mass, we should find creative ways to buy down the risk that don’t involve an enormous conventional overhead.

Combat support, for instance, needs to take on an expeditionary capability and approach. One example is to invest in the rapid development and fielding of an unmanned medical evacuation capability able to operate in austere environments. Light, mobile combat and service support can change our calculus about what it takes to fight in small teams on the modern battlefield.

The United States must find ways to reduce the logistics and support tail not only for our own fighting force, but also for our partners. “Small is beautiful”—and absolutely necessary. This applies far beyond current operations against the Islamic State. We must either adapt or remain ill-prepared for the fast-moving, offensive, chaotic and non-linear fights of the future.

This piece first appeared in CFR’s blog Defense in Depth here.