Sen. Mary Landrieu (J. Scott Applewhite/AP) Sen. Mary Landrieu (J. Scott Applewhite/AP)

Sen. Tim Johnson (D-S.D.) became the 54th U.S. senator to announce his support for same-sex marriage. He’s not running for reelection, so we can dispense with trying to figure out what it means for him politically. I can’t say the same for Sen. Mary Landrieu (D-La.). On Friday, the senior senator from the Bayou State made no sense when she told CNN that she was for marriage equality and against it.

“I’m a lot, like other people said, my views have evolved on this. But my state has a very strong constitutional amendment against gay marriage, and I think I have to honor that,” Landrieu said. Wait. So, she believes that same-sex couples should be able to marry, but because her state has etched discrimination into its Constitution, she cannot be on the right side of the issue and of history? She can’t show some leadership?

Look, I understand Landrieu’s political predicament. Stuart Rothenberg at Roll Call dubbed her one of the two “most vulnerable incumbent senators” up for reelection in 2014. She is a Democrat in a state that went for Republican nominee Mitt Romney over President Obama by 17 points. And she barely held onto to her seat in 2008 by snaring 52 percent of the vote. Still, Landrieu’s constitutional amendment rationale for her muddled pronouncement is lame.

Like Louisiana, Ohio and North Carolina have constitutional amendments banning same-sex marriage and civil unions. The Buckeye State did so in 2004. The Tar Heel State followed suit last year. But that didn’t stop Sen. Rob Portman (R-Ohio) and Sen. Kay Hagan (D-N.C.) from announcing their support for marriage equality.

Portman was the first sitting Republican senator to take this position. Even though he is a powerhouse in the GOP establishment and was elected to the Senate in 2010 with 57 percent of the vote, he is in a party that has seen many a safe, conservative legislator taken out by a challenge from his or her right. He is up for reelection in 2016. Meanwhile, Hagan faces the voters in 2014 in state that instituted its constitutional ban with 61 percent of the vote. It is also a state her fellow Democrat, Obama, won in 2008 by 0.3 percent of the vote but lost to Romney in 2012 by 2 percent.

I have long argued that the civil rights of a minority should not be put on the ballot. Implicit in that view is that those rights ought to be conferred by the courts, which has a history of handing down rulings that make us embrace our better angels. But depending on the courts is a last resort. The duly elected representatives of the people should be making these tough decisions. Supporting the right of same-sex couples to marry is one of those tough decisions that requires leadership. Landrieu fails this leadership test.

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