This article is from the archive of our partner National Journal

Gov. Scott Walker wants to be president and is a serious contender for the job. But nobody who wants to be taken seriously for the presidency can duck a question like, "Do you believe in evolution."

"I'm going to punt on that as well," the Wisconsin Republican said in response to a question in London about whether he was comfortable with the idea of evolution. "That's a question that a politician shouldn't be involved in one way or another."

My tweet drew a series of responses from Walker's corner, some thoughtful and some angry. Many people argued that the question isn't relevant.

I can think of at least two reasons why the question relates to Walker's unofficial bid for the GOP nomination. First, there are virtually no questions that are out of bounds for a presidential candidate. Think of a campaign as a lengthy interview for a job with 300 million bosses, each with a singular set of standards for making a decision. What might be a stupid question to 99 percent of votes ("Boxers or briefs?") might matter to somebody.

Presidential campaigns are a severe test.  As CNN's John King said on "Inside Politics" today, if you want control of the nuclear codes, be prepared to answer anything.

In this case, the question is directly related to the job Walker wants. A president's view on evolution would influence his or her position on climate change, precision science, stem cell research and scores of other issues connected to one of the most fundamental findings of the modern age.

Others defending Walker called the stories about his dodge another example of media bias.

Like most independent-minded voters, I'm tired of hearing both Republicans and Democrats excuse their leaders' mistakes by saying "the other side" is worse or gets better treatment. Republican voters should be the first to demand more of Walker than they've seen from Democrats. Don't let him hide behind you. Don't cover for his duck.

Walker tried the weasel route, telling Twitter followers, "It's unfortunate the media chose to politicize this issue during our trade mission to foster investment in Wi."

No, sir. It's unfortunate that a man who had the political courage to defy public employee unions is afraid to answer a simple question. Or maybe you're not so courageous. Your attempt to clean up the flap on Twitter didn't work because your tweet doesn't answer the question.

Who made this an issue? You, sir.

As a leader, Walker has a responsibility to explain to his supporters that evolution is fact and it's not necessarily a contradiction of their religious faiths. Nearly half of GOP voters do not believe humans have evolved over time, according to a Pew Research Center poll conducted last year. The percentage of GOP voters who believe in evolution has dropped 11 points in four years.

Walker also ducked questions about the Islamic State, Ukraine, and the United Kingdom's role in the European Union, saying it's inappropriate to undermine the U.S. president while abroad. That is an understandable "“ even admirable "“ position to take, and is consistent with then-Sen. Barack Obama's cautious approach to U.S. policy during his 2008 trip abroad as the Democratic nominee.

Republicans have convinced themsevles that Obama got preferential treatment from the mainstream media in 2008. I will concede the point for the sake of argument: Media bias is no excuse for Republicans who enter the arena unprepared or unwilling to field every question.

If you want the job, you've got to fill out the questionnaire.

This article is from the archive of our partner National Journal.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.