Throughout our history, the years immediately following military conflicts have often proved rich in reform. Four years after the war for independence, the Articles of Confederation were scrapped for the Constitution, which created a far stronger central government with a clear commander-in-chief. 

After the Civil War, the nation passed sweeping amendments to the Constitution guaranteeing civil rights, created the first social welfare program and took strong steps to unify the expanding nation, including the Transcontinental Railroad.

 The years following World War II proved extraordinarily productive. The institutions which guide our national security policy to this day were created, including the National Security Council, the Department of Defense and the Central Intelligence Agency.

The years from 1945 to 1951 also saw the creation of the United Nations, NATO, the world trading system and a major foreign assistance program.

There are clear lessons from our involvement in Afghanistan and Iraq.

First, the face of war has changed. Technology offers the opportunity for standoff attacks with drones and cruise missiles. These weapons demand little sacrifice and insulate us from the consequences of their use.

Second, while these weapons can be very effective, they do not and cannot substitute for “boots on the ground.” It is not possible to win wars from the sky alone; opponents sense that we are unprepared to make major commitments of blood and treasure to achieve victory.

Third, our opponents will not attempt to defeat the United States by matching force against force. They will adopt rapidly changing, asymmetric responses to U.S. power.

Fourth, it is far easier to overthrow governments — as we did with the Taliban in Afghanistan and Saddam Hussein in Iraq — than it is to replace them with stable, decent regimes which look after the interests of their people.

Fifth, modern stand-off technologies have vastly strengthened the power of the president. Presidents can use these weapons and argue we are not really at war. The constitutional power of Congress to declare war has further eroded.

Sixth, while our friends and allies will help us in limited ways, the U.S. needs to lead if success is to be achieved.

The authors of this article worked for opposing political parties in Congress and the executive branch. Yet we agree on broad policy reforms called for in the face of these lessons learned from Afghanistan and Iraq.

First, technology will continue to drive changes in both battlefield and non-battlefield tactics. We need robust funding for cybersecurity defense against foreign threats and for offensive cyber capabilities, as well as more effective communication strategies for countering enemy propaganda.

Second, Congress must take timely steps to combat its growing irrelevance on decisions about war.

War has become the business of a specialized niche of American society — the president and the voluntary military forces. The American people — as opposed to our warriors and their families — have sacrificed nothing. Legislators have been largely unaccountable. We have borrowed the money for wars; we have been unclear about the ultimate objectives; and Congress has taken a pass on playing any constructive role in shaping American policy. 

Congress should adopt a long-term defense budget that sufficiently funds U.S. defense needs — without borrowing funds from future generations.

Congress should compel the president to reduce the size of the National Security Council staff and return authority to accountable Cabinet departments. Congress should make clear that as a general rule, drone strikes should take place at the direction of the Defense Department. And Congress should enact specific authorizations for any ongoing use of military force.

Finally, it is long past time to update our alliance system. Our current system, oriented largely around NATO, is not working well. Most NATO countries have fallen well below the minimum agreed levels of defense funding and many have put in place unreasonable conditions for the use of their national forces.

Vacillating between this outdated structure and vague coalitions of the willing (as against ISIS) is unlikely to produce meaningful contributions from our friends and allies.

American politicians might wish that technology did not complicate their jobs, that the U.S. could take a smaller leadership role in the world, and that legislators could avoid any accountability for war policies adopted by the president. This is understandable  — but unacceptable and inconsistent with the hard lessons that their predecessors learned from America’s wars.

Gerry Warburg and Jeff Bergner teach classes on U.S. national security policy in the Batten School of Leadership and Public Policy at the University of Virginia.