Scott Walker, left, and Donald Trump during a break in the Republican presidential primary debate on Aug. 6, 2015, in Cleveland. (Mandel Ngan/AFP/Getty Images)
Opinion writer

This is what happens when you try to trump the Donald.

Scott Walker has for two decades won primary elections by refusing to allow any Republican to outmaneuver him on the right. So when Donald Trump, father of the Central Park ice rink, began skating circles around the Republican presidential field with his perfect execution of hard-line conservative positions, the Wisconsin governor tried to keep up by attempting more daring ideological leaps.

But in recent days, Walker has spun himself into a triple axel — and landed on his face.

First, asked by NBC’s Kasie Hunt whether he supported ending birthright citizenship — a constitutional principle in place since the Civil War era — Walker said: “I think that’s something we should, yeah, absolutely, going forward.”

Later, asked by CNBC’s John Harwood to clarify his position, Walker retreated. “I’m not taking a position on it one way or the other” until the border is secured, he said.

Finally, on Sunday, Walker said without qualification that he would not seek to repeal the 14th Amendment, which grants citizenship to those born on American soil.

The reversal, like Jeb Bush’s multiple positions on Iraq voiced in a single week this spring, produced much derision, but I have sympathy for Walker: The same would happen to anybody who tried to overtake Trump on the right.

Attempting to out-conservative Trump is folly — even if the guy is a former liberal who nakedly reinvented himself for this campaign. Trump, if he is thinking about anything, is not thinking about preserving his electability should he somehow win the Republican nomination. He is taking the most conservative positions possible on a range of issues — and otherwise viable contenders are doing themselves damage by trying to match him.

Louisiana Gov. Bobby Jindal last week echoed Trump’s call for ending birthright citizenship for illegal immigrants, even though Jindal, born to legal immigrants, might be considered an “anchor baby” who benefited from birthright citizenship himself. And Bush, who had taken pains to establish a moderate position on immigration, embraced the “anchor baby” term that offends many Latinos.

Nobody has been hurt by Trump more than Walker, who has seen his support drop nearly in half in the last month, to single digits. After his flat performance in the debate, he lost his longtime lead in Iowa. His donors and supporters are jittery, and, as my Post colleagues Jenna Johnson and Sean Sullivan reported last week, he tried to reassure them with a vow to emphasize his conservatism with more passion.

That could explain the birthright-citizenship fiasco. A day after Trump declared his opposition to granting automatic citizenship to those born on American soil, Walker embraced the same position, only to jettison it six days later. Though such a stance is popular with the Republican primary electorate, it would doom a Republican nominee with the all-important Latino vote just as surely as Mitt Romney’s “self-deportation” call did in 2012.

Republican presidential candidate Scott Walker unveiled a new health-care proposal that calls for repealing Obamacare. (Reuters)

Walker has been successful over the years by refusing to leave any room to his right. He had originally spoken favorably last year about the Environmental Protection Agency’s proposal to regulate carbon-dioxide emissions from coal power plants, but then he reversed course. In 2010, he opposed the harsh immigration law in Arizona but backed down only days later when besieged by criticism.

He had, in 2013, supported a pathway to citizenship for illegal immigrants, but he reversed himself earlier this year. Also in 2013, he said he had no interest in “right to work” legislation and called it a distraction, but earlier this year he signed such a bill. In 2014, he ran an ad saying that while he’s pro-life, he supported legislation leaving the final decision on abortion to a “woman and her doctor.” But now he says he opposes abortion in all cases, even to protect the life of the mother. Also in 2014, Walker said the issue of same-sex marriage wasn’t a priority for him and should be left to the courts. Now he backs a constitutional amendment giving the power to decide on gay marriage to the states.

The Wall Street Journal’s Reid Epstein last week traced back to 1993 Walker’s positions on issues such as abortion, immigration and the death penalty (which Walker supported in 2006 after long opposing it). “At each step in the Wisconsin governor’s career, he has run against Republican opponents with one overriding strategy: Never letting anybody get to the right of him,” Epstein wrote.

But now Walker’s time-tested tactic is failing him, for a simple reason: There is no way to outflank Trump on the right. Trump, without a care for Republicans’ long-term electoral viability, is making a parody of the conservative-dominated Republican primary process by embracing the most extreme positions, particularly on immigration. The showman has reduced GOP politics to absurdity — and you can’t trump that.

Twitter: @Milbank

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