President Obama belatedly will speak to the country on Tuesday in a last-ditch attempt to avoid a crushing defeat in one or even both houses of Congress on the resolution for military action in Syria. The speech is problematic for two reasons.

President Obama (Jason Reed/Reuters) President Obama (Jason Reed/Reuters)

First, it is not clear what the president actually wants to do, and maybe he doesn’t even know. We’ve heard from him that he envisions only a “shot across the bow.” He clings to the notion he was elected to “end wars, not to start them.” (Actually one war was over — his contribution was to precipitously withdrawal all forces — and he promised to prosecute the other successfully.) However, this week his advisers have begun to formulate an actual strategy, that is to “degrade” Syrian President Bashar al-Assad’s forces, which will inevitably tip the playing field toward the Syrian Free Army.

It is hard to give a speech when you don’t know what, ultimately, you want to do. Stick with it until Assad’s forces are crippled or do the bare minimum to preserve the façade of effectiveness? And what about finally arming the opposition?

Second, presuming the president knows what he wants to do, he has to decide what the speech can accomplish and who his primary audience is. If it is to rescue himself from repudiation by dovish Democrats, he’ll need to emphasize the “limited” part of his plan. If it is to win over Republicans and middle-of-the road Democrats who don’t see a purpose in what has been presented so far, he’ll need to stress how “robust” the effort will be.

As for the public, overwhelmingly opposed to doing anything, a single speech is unlikely to move opinion. The president has been singularly unsuccessful in moving public opinion on policy matters (e.g. Obamacare). In this case, there is no reason to believe after two years of telling the public we could and should avoid Syria’s civil war that he will be able to turn voters around.

Then there are the mainstream and liberal media, which have been entirely unwilling to carry the president’s water on this one. He’s been savaged for ineptness and chastised by anti-war pundits. A president once revered by the press and still exquisitely sensitive to criticism may be desperate for some favorable reviews. Does he try to dazzle with high-minded appeals? His usual gambit, calling into question Republicans’ motives, won’t work here, given that he’s relying on many of them to make up for the deficit with Democrats.

In truth, the only way the president will win over votes is by personal appeals to Democrats to save his presidency. He can’t very well do that in a speech to the country. What is left, then, for Tuesday?

Well, when all else fails he might resort to the truth: This is more about Iran than Syria. It is, after all. Failure to respond here is a flashing green light for Iran and its proxies Hezbollah and Hamas to pursue or threaten to use WMD’s. To signal now that a regime can survive after WMD use would be fatal to our efforts to deter Iran. It would panic our allies and set off an arms race in the region. The international chemical weapons ban would be in tatters.

As a political matter, there is a huge consensus in Congress on the need to stop Iran’s ambitions. That consensus is bipartisan. Iran, therefore, is an appeal that won’t lose votes and may unify the public and Congress.

Obama may not have dwelled on this point, but Secretary of State John F. Kerry has, and the pro-Israel community has sounded the alarm on this very point.

The formula here is simple: Talk to the public about Iran and plead with Democrats in private. It may not work, but that is the only reasonable chance to solve a knotty problem of Obama’s own making.