Over the past 40 years, the one consistent face of war with which we have been confronted is irregular warfare. In parallel, one consistent threat to our security has been our inability to retain the lessons in irregular warfare that we learned on the battlefield.

It is happening again.

From 1965 to 1975 we built knowledge and skill in this area in a decade of conflict in Vietnam. As a result of domestic politics and war fatigue, we abandoned these skills and knowledge of asymmetric warfare, returning instead to the comfort of a more conventional enemy.  We then improvised through shorter conflicts in the ’80s and ’90s in dealing with a post-Noriega Panama, a destabilized Somalia, and a post-conflict Balkans with mixed results.

In 2006 we came face to face with the reality that we faced two tough low intensity fights in Iraq and Afghanistan. We were losing ground in both. Only a crash push in counterinsurgency and stability doctrine, operations, training, and equipment allowed us to turn the tides in those conflicts.

Even so, we paid a terrible price as we lacked the force structure and strength to allow for a sustainable force generation and recovery process. Our Army and Marine Corps families saw our loved ones pull five, six and even seven tours of combat over a decade. We also discovered our equipment kit was grossly insufficient for the low intensity threat and relied on expensive rapid procurements in MRAPs, body armor, and urban warfare systems to close our systems gap.

Given this, one would expect that serious national security analysts inside and outside the Pentagon would champion the need to sustain the training, force structure, and asymmetric systems of the past 10 years, right?

Wrong. There is now almost unstoppable momentum from sources to significantly reduce Army and Marine Corps force structure and to refocus the force on "core competencies," which is code for “conventional warfare.” This thinking will eliminate many of the programs that emerged as essential to success in irregular warfare. It is based in the misguided notion that we simply won’t “do” large scale, irregular warfare any more.

Yet that is the very mission we have done repeatedly for the past 40 years. It’s the mission ordered time and again by Republican and Democrat presidents alike. It’s the mission that our enemies know they can win because we never prepare for it.

Cutting ground force training and programs is national security planning based on domestic politics. It fails to take into account recent history and the very real future challenges that today’s young soldier or Marine is likely to see in his or her years of service. We cannot wish away instability, failed states, post-conflict instability, large refugee flows, genocide, terrorism, humanitarian catastrophe, regime change, and the need for intervention.

Part of the problem is lop-sided priorities among Air, Sea, Land and Cyber warfare. Air and Sea already have overmatch dominance while Land and Cyber capabilities are challenged every day. We cannot continue down this path – or worse let our land forces get smaller and less capable in irregular warfare. Only our enemies will thank us for this.

This type of blind approach to security planning will not keep us from sustained low intensity conflict. But it will ensure that we are, yet again, unprepared and under-dominant on a battlefield that is as much about weapons and armor as it is about ideas and the use of smart power to stabilize areas.

We cannot afford to send our soldiers and Marines into harm’s way again without the equipment, training and understanding of irregular warfare they will need to fulfill tomorrow’s missions.

Simply hoping that they will never need any of these is not a plan to bring them safely home; robust full spectrum unified land operations remain imperative for the 21st century.

Gen. Gordon Sullivan served as the 32nd Chief of Staff of the U.S. Army and is now the President and Chief Operating Officer of the Association of the United States Army. Dowling served as Director for European Affairs at the National Security Council and is now president of IDS International, a “smart power” government services firm.