Hillary Rodham Clinton (Carolyn Kaster/Associated Press)
Opinion writer

President Obama, so often cool and cautious in his language, gave a full-throated roar on trade last week, saying thatSen. Elizabeth Warren was “ absolutely wrong ” in her criticism of the Trans-Pacific Partnership and that “her arguments don’t stand the test of fact and scrutiny .”

I think Obama is right about the TPP, but there’s a larger point here about leadership. Governing is a contact sport. Presidents don’t accomplish great deeds without fighting for them. Often, that includes confronting rebellious members of their own party. And Obama’s tough stance seemed to have succeeded Thursday, as the Senate overcame a Democratic revolt and passed key bills to enable the TPP.

Modern presidents, from Lyndon Johnson to Ronald Reagan to Bill Clinton, have won big legislative victories when they similarly played political hardball. That’s something Obama has learned late in his presidency, but this toughness is visible now on issues that matter to his legacy, such as the Iran nuclear deal, Cuba and free trade. He’s ready to roll opponents, even if they’re his friends.

Which raises a question: What does Hillary Clinton believe about the Trans-Pacific Partnership or the Iran nuclear deal? You would assume that she’s supportive because she helped get both agreements started. But she has been a study in reticence — a trimmer checking the political winds, rather than a leader.

Clinton had it right in her memoir, “Hard Choices,” published last year: “The TPP won’t be perfect . . . but its higher standards, if implemented and enforced, should benefit American businesses and workers.” Is Clinton really running so scared from Warren that she’s ready to disown economic policies she helped shape? Does she think that running against Obama’s economic record will be good politics?

Clinton should put away the waffle iron when it comes to the Iran deal, too. As secretary of state, she launched the secret channel in Oman that passed the message that Iran could enrich uranium if it agreed to tight controls on its nuclear program. Her experience with such secret diplomacy is one reason she’s a compelling candidate. But she has been stinting in her comments so far about the Iran pact.

The progressive rebellion against Obama on the TPP is mystifying, not least because the factual basis for challenging the deal seems so thin. Labor is arguing that the agreement will be a job-sucking repeat of the North American Free Trade Agreement. But the TPP would actually fix many of the weak labor and environmental provisions of NAFTA, imposing tougher standards for Canada and Mexico as well as the other signatories of the 12-nation agreement.

A recent study by Jay Chittooran for Third Way, a centrist think tank, noted that the TPP, like the 17 other U.S. trade deals negotiated since NAFTA, includes “wide-ranging, and enforceable labor protections.” An alternative future, in which the TPP fails and China writes the rules for its Asian trading partners, would effectively mean “non-existent or watered down labor standards,” he wrote.

Warren’s stance, too, is puzzling. She has focused on the TPP’s use of an arcane mediation provision known as Investor-State Dispute Settlement, or ISDS. Though it has been part of investment agreements for decades, Warren claims ISDS gives “a special break to giant corporations.” But a recent study by Gary Clyde Hufbauer for the Peterson Institute for International Economics noted that firms have won only 29 percent of arbitrations under a system similar to ISDS that the World Bank has used since 1996.

But it’s Clinton’s rope-a-dope approach to the TPP that deserves most attention, because it highlights her vulnerability as a candidate. Her caution conveys the sense that she’s running because she wants to get elected, rather than as the exponent of a set of beliefs. Critics have argued that Clinton, similarly, sought to play by a special set of rules in her use of a private e-mail server while she was secretary of state and in the Clinton Foundation’s harvest of contributions from foreigners.

“I’ve run my last election,” Obama said a week ago. “The only reason I do something is because I think it’s good for American workers and the American people and the American economy.”

Clinton is still running, but she could take a political lesson from Obama. She needs to be a fighter. Avoiding the issues will only reinforce the sense that she is a hollow candidate. She should be taking credit for the good provisions in the TPP, not hedging her bets. She may be ready to run, but is she ready to lead?

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