Barack Obama’s redecoration of the Oval Office includes a nice personal touch: a carpet ringed with favorite quotations from Abraham Lincoln, John F. Kennedy, both Presidents Roosevelt, and Martin Luther King Jr. The King quote, in particular, has become a kind of emblem for him: “The arc of the moral universe is long, but it bends toward justice.” For all the carping about his every move, the only big problem with the Obama Presidency is the gap between what’s written on his rug, and what’s buried under it—the distance between the President’s veneration of moral leadership past and his failure, so far, to exhibit much of it himself.

Obama has had numerous occasions to assert leadership on values issues this summer: Arizona’s crude anti-immigrant law, the battle over Prop 8 and gay marriage, and the backlash against what Fox News persists in calling the “Ground Zero mosque.” These battles raise fundamental questions of national identity, liberty, and individual rights. When Lindsey Graham argues for rewriting the Constitution to eliminate the birthright citizenship clause of the 14th Amendment, or Newt Gingrich proposes a Saudi standard for the free exercise of religion, they’re taking positions at odds with America’s basic ideals. But Obama’s instinctive caution has steered him away from casting these questions as moral or civil rights issues. On none of them has he shown anything resembling courage.

Responding to the fight over the mosque, Obama has been characteristically legalistic and technical. At an Iftar dinner he hosted at the White House, the president supported the right of Muslims “to build a place of worship and a community center on private property in lower Manhattan”—itself a too-picky allowance. The next day, he hedged even further, telling reporters, “I was not commenting and I will not comment on the wisdom of making the decision to put a mosque there.” This sail-trimming, where a bold defense of freedom of worship was wanted, left it to the newly heroic Michael Bloomberg to instruct us, at his own Iftar dinner in New York, that the issue was “a test of our commitment to American values.”

With the Proposition 8 fight, Obama has fallen short in a different way, by his reluctance to join an emerging social consensus. Obama had previously criticized California’s Proposition 8, the ballot initiative banning same-sex marriage, as “divisive.” But his official position—which no one believes he actually holds—is that he is against legalizing gay marriage. Americans are changing their views on this issue with inspiring rapidity. Judge Vaughn Walker’s moving opinion provided an occasion for Obama to move to embrace the extension of equal rights to gay people. Instead, he slunk mumbling in the other direction. How dismal that America’s first black president will be remembered as shirking the last great civil rights struggle.

When it comes to immigration, Obama has largely failed to challenge the new nativism represented by Sarah Palin, Glenn Beck, and Arizona Gov. Jan Brewer. Yes, his Justice Department filed suit to block the implementation of Arizona’s harsh law. But in talking about the topic, Obama has remained restrained and self-referential (“I’ve indicated that I don’t approve of the Arizona law …”). He has said nothing moving or memorable about the place of immigration in American life, or the rights of noncitizens, including the rights of children to education and medical care, or the reality that 11 million undocumented residents can’t and won’t be shipped back where they came from.

Here, as elsewhere, the current politics don’t favor the liberal position. But read the rug: “The welfare of each of us is dependent fundamentally upon the welfare of all of us”—Theodore Roosevelt. Obama has let pass moment after moment—such as the recent Republican suggestion of revising the section of the Constitution that guarantees due process—to reframe the issue around terms of inclusiveness and justice.

Few would argue that defending liberal principles serves Obama’s short-term interests. Americans oppose the mosque 61-26 according to one recent poll, and support the Arizona law by an even wider margin. But even if some people don’t like Islam, or illegal immigrants, or gay weddings, they may respond to admonitions that our society is built around freedom of conscience and equal treatment under law. If he applied his literary gifts to these principles, it would give Obama’s depressed Democratic base something to be excited about. It could remind a grumbling nation what it liked about him in the first place.

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