First, the threat of regime change is designed to deter Assad from using chemical weapons. It is essential for the United States to reaffirm the norm that using chemical weapons is wrong, is immensely dangerous, poses a direct threat to U.S. and international security, and will be dealt with harshly.

Second, the prospect of regime change is designed, simply, to get Assad to focus on his own survival, and to use that fear to change his behavior. Nothing so focuses the mind, loosely quoting the Englishman John Donne, as the prospect of being hanged in a fortnight.

Third, the critical instrument of policy is to create fear in Assad’s mind—the fear that today, tomorrow, next month, just about anytime, or maybe never—a precision-guided munition will end his life. As we learned in fighting against Al Qaeda, it is vastly more difficult for terrorists to plan attacks when they constantly worry about being killed. We also want to amplify the fear in Assad’s mind that arises from the element of surprise. Why create certainty in Syria about what America will do when uncertainty reinforces our core strategy and weakens Assad? The less Assad and his people know about what the U.S. plans the better.

Fourth, it is essential to undermine support from Russia and Iran for Syria. A central objective of U.S. policy must be to demonstrate that these authoritarian patrons of another authoritarian state are unreliable allies. The long-term benefits of identifying Russia and Iran’s leadership as untrustworthy supporters will pay immense dividends by making the world safer and more secure.

Fifth, the threat of regime change demonstrates vividly the deeply personal costs to government leaders if they order the use of chemical weapons. It will reaffirm the U.S. commitment to the norm, which holds that civilized states do not use such weapons of warfare against their own innocent men, women and children.

In the end, the failure to put the instrument of regime change on the table demonstrates a lack of resolve, commitment, or weakness—all of which will be interpreted by friend and foe alike as acquiescence in the face of states using chemical weapons.

U.S. Needs New Model of Regime Change

Why, you ask, is it time to think seriously about regime change?

Regime change puts the onus of responsibility directly on Syria’s President Assad. The threat of regime change alone may persuade Assad to stop these attacks. Better yet, it may embolden moderate rebels (with appropriate assistance from the West) to defeat the Syrian government—and weaken the influence of Russia and Iran.

For now, I urge policymakers to forget everything they have learned about regime change. Forget about regime change in terms of using U.S. military forces to invade a country, change its government and build a new government with boots on the ground, and assume all responsibility for the future of Syria—including the prospect of a sectarian civil war in which many Americans would die if policymakers were to put forces in Syria. Fundamentally, we need to move beyond this post-Iraq, post-Afghanistan “old think.”

In the end, the reckless decision to use chemical weapons against the Syrian people provides four perfect opportunities: undermine a dangerous regime, reinforce the norm of not using chemical weapons, undermine states such as Russia and Iran whose policies are making matters worse, and ultimately do the right thing for the international community and the United States.

By employing the regime-change option, the U.S. and its allies can stop the dithering that signals their indecision. It is not becoming of the world’s sole remaining superpower to be showing a lack of resolve.

Ultimately, using military force to weaken and change the regime has the principal benefit of removing President Assad while allowing the Syrian people to work out the future of their state—however that evolves.

Simply stated, the best option for the United States is to keep regime change on the table.

William C. Martel is an Associate Professor of International Security Studies at The Fletcher School of Law and Diplomacy at Tufts University. Martel is the author of Victory in War: Foundations of Modern Strategy (Cambridge UP, 2011). He is also completing a book on the evolution of grand strategy. You can follow him on Twitter: @BillMartel234.