One of the strongest arguments for voting “yes” on authorizing strikes against Syria is that a “no” vote will do significant damage to the credibility of the United States.

“It is to President Obama’s great discredit that he has staked his credibility on a vote whose outcome he failed to game out in advance,” Ross Douthat of the New York Times has written. “But if he loses that vote, the national interest as well as his political interests will take a tangible hit: for the next three years, American foreign policy will be in the hands of a president whose promises will ring consistently hollow, and whose ability to make good on his strategic commitments will be very much in doubt.”

That’s a very reasonable case. But it’s one that’s worth examining with some care.

It’s quite true, and I believe quite regrettable, that American credibility will suffer if the president is denied the authority he seeks. But it’s not clear to me that if Mr. Obama gets the authority to strike Syria, American credibility will be that much greater.

I say that for several reasons, the most obvious of which is that the strike the president intends to deliver is not meant to alter the balance of power in Syria. The president himself has described what he intends to do as a “shot across the bow” — a revealing locution, since a “shot across the bow” means a harmless strike. Mr. Obama has signaled, in as many ways as he can, that a strike in Syria is meant to be de minimis. And Secretary of State John Kerry, in London earlier today, put it this way: “We will be able to hold Bashar al-Assad accountable without engaging in troops on the ground or any other prolonged kind of effort in a very limited, very targeted, short-term effort that degrades his capacity to deliver chemical weapons without assuming responsibility for Syria’s civil war. That is exactly what we are talking about doing – unbelievably small, limited kind of effort.” [emphasis added].

Is it possible that the president unleashes his inner John McCain and decides to alter the course of the Syrian civil war? I suppose so, but let’s just say it’s highly unlikely. Let’s assume, then, that the president does what he’s said he would do. How much credibility would that have?

Abdel Jabbar Akaidi, the Free Syrian Army’s chief for Aleppo province, has said, “a light strike would be worse than doing nothing. If it’s not the death blow, this game helps the regime even more. The Syrian people will only suffer more death and devastation when the regime retaliates.” Senator McCain has said the same thing.

So the option isn’t between no strike at all and a massive strike that delivers a crushing blow to the Assad regime. The choice is between no strike and, if the president and his secretary of state are to be believed, an “unbelievably small,” inconsequential one. Are we then supposed to believe the latter would salvage America’s credibility? That the Iranian regime — which has not been slowed by anyone or anything to date — will be dissuaded from pursuing nuclear weapons after a strike against Syria that was only undertaken because the president had boxed himself into a corner and from which Bashar al-Assad will emerge undamaged and still in power? That is simply implausible, especially given Mr. Obama’s larger record of irresolution and incompetence.

No president in my lifetime has been more ambivalent about the use of American power; and if Mr. Obama does strike Syria, Peggy Noonan poses the right question: “If we bomb Syria, will the world say, ‘Oh, how credible America is!’ or will they say, ‘They just bombed people because they think they have to prove they’re credible’?” The restoration of American credibility will probably have to await a new American president (think of Reagan following Carter).

And what will Mr. Obama’s strike succeed in doing? It will involve us in a brutal and immensely complicated civil war that would test the skills of even the greatest statesmen. Dexter Filkins, one of the finest war reporters in America, has said the civil war in Syria is “a more violent and unpredictable conflict than any I’ve ever seen.” The rebels, he says, are scattered and divided. Al Nusra Front, a sister organization of al Qaeda, has “emerged as the strongest group among many.” Ambassador Ryan Crocker, one of America’s finest diplomats, has written that the opposition to Assad “lacks cohesion and organization” and agrees that the most radical elements have demonstrated the greatest discipline. “The hard truth is that the fires in Syria will blaze for some time to come,” according to Crocker. “Like a major forest fire, the most we can hope to do is contain it.”

There are other, serious interpretations of the circumstances on the ground. But even advocates of a military strike against Syria would concede, I think, that the conditions for a political settlement simply are not in place. And what exactly has President Obama achieved to warrant confidence that he can navigate these violent waters and positively influence events in Syria? His mastery of events in Egypt? Iraq? Iran? Libya? Afghanistan? His reset with Russia? His skillful handling of our allies like Great Britain? The Czech Republic and Poland? Israel? Please cite for me the example we can look to that will inspire confidence that the president is up to the challenges posed by Syria. If such an example exists, it has eluded me.

Which brings me to my final point. As a person who favors American engagement in the world — who has supported American interventions over the years, who believed we should support the relatively moderate Syrian rebels some time ago and who supported President Obama’s surge in Afghanistan — my concern is that for America to become militarily involved in Syria at this stage may well end up doing grave damage to the cause of internationalism. It could do more, in fact, to help the quasi-isolationist movement in the GOP than anything else — including denying Mr. Obama the authority he seeks.

For the United States to go to war with around a quarter of the nation supporting intervention — even before the bombing has started — is a very dicey and unsettling proposition. If we get militarily involved in Syria and things go badly — which I think is likely, given both the intrinsic nature of the conflict and the ineptness of our commander-in-chief — it will strengthen, not weaken, the Rand Paul wing of the GOP.

To put it another way: Those who favor an active role by America in the world — hawks who have spent their lives rightly resisting the “America Come Home” siren call — need to be wise in their counsel. Because if the next military engagement isn’t well thought out, well executed, and doesn’t lead to a relatively swift and decent outcome, the blowback could be intense. Syria could do to America what George McGovern never could.

In saying all this, I recognize that I’m out of step with many people whose judgment I respect and with whom I have stood shoulder-to-shoulder over many years. Nor do I think the decision on the authorization of force is an obvious one. There are legitimate arguments to be made on both sides and potential downsides to each course of action. On top of that, we’re talking about predicting how a series of events will unfold in a Middle Eastern nation riven by war, sectarian divisions and hatreds that reach back generations, which ought to elicit from us a touch of humility rather than certitude.

All we can do, all we can ever do, is to bring our best judgment to bear on the situation we face. The issue hinges on whether one believes a pointless and ill-considered strike by this president against the Syrian regime does more or less damage than a congressional “no” vote that would make America even more of a non-entity in international affairs.

I will confess that I’m not fully comfortable with my position. But I’m more comfortable with it than the alternative.

Peter Wehner is a senior fellow at the Ethics and Public Policy Center.