Deputy editorial page editor

Shortly after Bob Corker (R-Tenn.) was elected to the Senate in 2006, I found myself seated next to him at a dinner. Corker's race against Harold Ford Jr. had included a Republican National Committee ad with ugly racial overtones, and I asked the new senator what he had learned about running against an African American opponent.

I can't recall what Corker said, but I do remember what happened after: The next afternoon, my office phone rang. It was Corker on the line, no aide placing the call, saying he had been thinking about my question and felt he hadn't given me a full enough answer.

This was, as it turned out, quintessential Corker, unassuming, thoughtful, decent and diligent. Which is why Corker's announcement Tuesday that he would not seek a third term, while not exactly a surprise, was such a disappointment — especially coming, as it did, hours before racist homophobe and disgraced judge Roy Moore won the Alabama Republican primary for the Senate.

The Senate — and the Republican Party — needs more Bob Corkers, fewer Roy Moores. The trend line is not promising.

Certainly, Corker is no liberal squish — he is not even a moderate along the lines of Sen. Susan Collins (R-Maine). You're not going to find him casting a vote against Education Secretary Betsy DeVos or to save the Affordable Care Act or to expand background checks for gun buyers.

Yet in an era of virulent partisanship, he has been unwilling to cede the possibility of bipartisan cooperation, whether with Mark Warner (D-Va.) on housing finance reform or with Ben Cardin (D-Md.) to ensure a Senate role in approving the Iran nuclear deal.

Voluntarily relinquishing power is an alien concept in Washington, so Corker's retirement announcement felt particularly jarring; he is not only an incumbent senator, but chairman of the Foreign Relations Committee. Yet Corker, 65, is not a traditional Washington creature. He came here saying he expected to serve just two terms, and flirted with leaving after one.

"I have always felt like I was a free agent," he told me in a phone interview Thursday. "I have never felt particularly tied to electoral outcomes because I never expected to be here that long."

So it is possible to misread or overinterpret Corker's decision as a sign of the poisonous times, of frustration with the gridlocked legislative environment (although Corker freely admits to being as frustrated as the next senator) or about having to fend off a primary challenge (a notion that Corker summarily dismisses, noting that he had ample cash and had faced only "third-tier" challengers).

But to talk to Corker is also to get a glimmer of the excitement — perhaps even relief — he feels at being entirely liberated from political concerns, and of the role he can play in his remaining 15 months.

Speaking of the environment today where any incumbent who dares seek bipartisan compromise is in danger of being primaried from the party's extreme flank, Corker said: "No matter what anybody says, you're kind of held hostage, aren't you? You get in a tough, tough primary and as principled as you are, it's in the back of your mind." At "the peak of my producing time here," Corker said, "I didn't want to do anything that would in any way take away from me making the most difference possible."

One of those differences could involve the fate of tax reform, Republicans' last best hope for a legislative win. Corker voted to proceed with a budget framework that allows for $1.5 trillion in tax cuts — but insists that he won't agree to a final deal that adds to the deficit.

"Once the election occurred in November, it's like a light switch went off and we went from caring about deficits to it being party time," Corker said of fellow Republicans. "At the end of the day, if I think it adds one penny to the deficit, I'm not going to vote for it. . . . I'm going to lay on the railroad tracks and keep it from happening."

The Senate will be worse off for Corker's eventual departure. But his decision to leave may have the paradoxical effect of making it a better place over the 15 months that remain.

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