There's an argument, made by Ezra among others, that Obama is allowing Rick Warren to give the invocation at his inaugural in order to "reach out" to Evangelicals. Maybe, in the same way George W. Bush thought a gospel choir at the 2000 convention would "reach out" to black folks. Like Bush, to the extent he's reaching out, he's reaching for a fairly small middle, which seems odd since, you know, the election is over.
I think it's more likely that he's marginalizing Warren's rivals among the Evangelical leadership. Warren is not actually any less conservative than Dobson or Robertson or anyone else. He is less partisan. His views on abortion and violence are similarly inconsistent, with one being abhorrent and the other acceptable. (The power and legitimacy of the American state, it seems, turns the conservative faithful into moral relativists.) But Warren has shown a tendency not to attack individual political figures the way his peers have, and so Obama has made the decision to elevate Warren at his rivals' expense. I had an argument with my colleague Brentin Mock yesterday about Obama's decision, where he pointed out that someone else would be occupying Warren's leadership role if it wasn't Warren, and given the alternatives he's the best choice.
None of this really changes the fact that mainstreaming homophobia is inexcusable, and that Warren does not deserve to share a stage with the Rev. Joseph Lowery. The contrast between Warren's celebrity and Lowery's life fighting for civil rights is absolutely staggering. It's possible to interpret the decision to include Warren and Lowery as another Lincoln "we are not enemies but friends" moment, an attempt to bring the religious right and religious left together. The only problem is the most offended parties, the LGBTQ community and the women Warren equates with Nazis, are not in any symbolic sense present to make the choice to be friends or enemies. Had Obama, say, chosen a gay pastor and forced Warren to make the difficult decision of whether or not to appear, the situation might be a bit different. At the same time, Lowery's presence as a symbol of his generation's sacrifice is absolutely necessary. Obama simply wouldn't be able to run for president without men like Joseph Lowery.
Even if one reads Warren's presence as a cold political calculation, it's hard to see why the LGBTQ community wouldn't be outraged at being exploited for the purpose of cultural triangulation. Obama isn't a homophobe, but you gotta wonder how long the LGBTQ community has to wait before they get a president who thinks homophobia is unacceptable. What ultimately matters, I suppose, is what Obama decides to do while in office. Lincoln was a white supremacist, but he still freed the slaves. Lyndon Johnson tried to throw Fannie Lou Hamer out of the 1964 Democratic convention to avoid alienating the Dixiecrats, and he still signed the Civil Rights Act. Symbolic moments like the inauguration are less meaningful than what Obama actually decides to do while in office, but they're far from meaningless.
UPDATE: Brentin says I misunderstood what he meant and that he never said Warren was the "best" of the options.