Peter Wehner is absolutely correct to lambaste President Obama and his failure of leadership on Syria. There is nothing more corrosive to U.S. credibility than voided red lines. The fact that Obama turned his back on the Syria chemical weapons red line just after the 25th anniversary of Operation Praying Mantis, the largest surface naval engagement since World War II and President Reagan’s response to Iranian mining of the Persian Gulf, shows just how far American credibility has tumbled in recent decades.

Republicans are wrong, however, to pressure Obama to begin provision of lethal arms to the Syrian rebels. If the United States could not vet two Chechen immigrants living in Cambridge, Massachusetts, with regard to their ties to radical Islam, it is doubtful that U.S. authorities can do so with regard to Syrian personnel who do not speak English and for whom background checks and vetting would be considerably more difficult, as they live in a war zone. Nor can the United States count on Turkey which, under the leadership of its unabashedly Islamist prime minister, has made a policy decision to support the Nusra Front, a group which the United States considers to be an al-Qaeda affiliate.

While the United States’ support to Syrian rebels might once have enabled more moderate factions to establish control, those days have long since passed. It is a conceit among many American politicians to believe that they can engage in extended debate without regard or particular attention to the fact that the world does not stop while they carry on. Nor is there any evidence that those whom the State Department chooses to engage have any sway on the ground.

So where does that leave the United States? Credibility is important, and so something needs to be done. Some might seek a Clinton-like solution where, in the wake of the 1998 East Africa embassy bombings, he shot a couple cruise missiles into Sudan and Afghanistan. Destroying some key Syrian military infrastructure—an airfield for example—might symbolically show that Obama’s word isn’t totally empty, but it would not enhance U.S. national security.

An Assad victory—with his support for Iran and Hezbollah—is like dying of cancer, while a rebel victory—with the rise of al-Qaeda affiliates within its midst—is like dying of a heart attack. It’s time for the United States to take care of itself. The key problem from a U.S. standpoint is the chemical weapons depots. These cannot be dismantled as was Libya’s WMD program. Back in 2003, it took U.S. personnel about ten days, and that was without anyone shooting at us. Perhaps the best course of action would be to bomb the depots from above (leafleting ahead of time to warn local residents) as contamination could be significant, but neither side in the Syrian civil war can be trusted with chemical weapons access.

In the debate over red lines, however, the true lesson is being missed: The time to worry about a murderous regime with chemical weapons or other means of mass destruction is before they acquire that capability. When Colin Powell, John Kerry, and Nancy Pelosi traipsed to Damascus in the past decade, they believed that either incentives or their own persuasive power might convince Assad to come in from the cold. Assad, however, saw his American interlocutors as useful idiots, whose presence and belief in diplomacy allowed him the time and space to augment his arsenal. Obama may have hemorrhaged U.S. credibility, but the real error started before he even took his oath of office.