President Obama’s abrupt decision to seek authorization from Congress before ordering attacks on Syria has elicited speculation about what motivated this apparent change of heart. After all, the president didn’t seek Congress’s approval before ordering attacks against Muammar Qaddafi’s forces in Libya in March 2011. Back then, members of the administration claimed—erroneously, as Louis Fisher points out here (.pdf)—that they had all the authority they needed from UN Security Council resolution 1973. It was a very thin reed on which to build a case for war, but administration officials teamed up with hawks on both the left and right to turn aside the objections of dovish Democrats and “Kucinich Republicans,” as the Wall Street Journal’s editors called them.

Obama couldn’t shelter behind the UN this time around, and Congressional opposition arose much faster and stronger than I anticipated as recently as last week. Even some Democrats, most notably Virginia’s Sen. Tim Kaine, voiced concern about the president’s apparent intention to circumvent the people’s elected representatives. The British Parliament’s rejection of Prime Minister David Cameron’s call for air strikes was a further blow, both in that it denied the United States a credible ally (only France remains), and highlighted the uncomfortable fact that most democracies have a debate before going to war.

So now the attention turns to Congress, with many members still on recess, but a number returning early to Capitol Hill for briefings and hearings. Those handicapping the sentiment in Congress claim that the president lacks the votes today to secure a victory, but he has a full week to change minds and twist arms. Some of the 190+ members who signed at least one of two letters, or issued a statement, calling on the president to go to Congress before launching an attack will be satisfied to have been included in the process. Sen. Kaine expressed this sentiment today. Party leaders may not whip the vote, but Obama will be assisted by the pro-intervention chorus, led by Sens. John McCain (R‑AZ) and Lindsey Graham (R‑SC), and by the signatories to this letter issued last week by the Foreign Policy Initiative. The pro-Obama team will include an unlikely ally: Weekly Standard editor William Kristol, who declared last night on CNN’s Anderson Cooper 360 that a vote against Obama would be effectively a vote for Assad. There will be more of this in the week ahead.

It will be hard for the opponents of intervention in Syria to prevail given that many Democrats can be expected to side with the president, and a number of Republicans still prefer the interventionists’ talking points, even if they know they are unpopular back home.

That last part might be changing, however, as the New York Times observed. Washington’s apparent disdain for the people who pay this town’s bills is what prompted the uprising now known as the Tea Party. Foreign policy is rarely a salient political issue, but challengers anxious to unseat an unpopular incumbent may add yet another vote that doesn’t reflect his or her constituents’ views to the bill of particulars that ends “which is why we should throw the bum out!”

The best arguments against intervention in Syria, however, hinge on the likely effects of the military operation itself, not on the politics of the day, or the precedent that it sets for the future. And here the opponents have a rich and growing body of work from which to draw. In addition to material from Cato (check back here often), see, for example, here, here, and here. Targeted cruise-missile strikes will not tip the scales decisively in favor of the anti-Assad forces, or at least not the ones who we would like to see prevail. The strikes are unlikely to deter Assad or others from using extreme measures when they fear for their regime’s survival, and are likely to encourage other countries to want a deterrent of their own. And, once those limited strikes fail to topple the regime, the advocates for more extensive U.S. involvement will call for more. The United States is, thus, likely to find itself deeply entangled in yet another civil war in the region. No wonder the American people remain overwhelmingly opposed even to what they are assured will be limited, targeted strikes. They have learned the right lessons of Iraq and Afghanistan, even if many in this town refuse to.

I look forward to a debate on the substance in the week ahead, and I hope that it doesn’t completely devolve into name-calling and oversimplification (naive, I know).