The last few days have offered some startling revelations about a running mate — Sarah Palin's running mate. For months, Republicans have been asking the ominous question: How well do we know Barack Obama? The GOP nominee's vice presidential choice raises another one: How well do we know John McCain?

McCain's central message all along has been twofold. The first is that he would keep us safe in a scary, hostile world. The second is that he would always do what is right for the country he loves, no matter what the political or personal cost.

The first theme is a favorite of Republican presidents, but McCain's background has made it especially potent for him. During the Republican primaries, he made a point of noting that he, unlike his rivals, had "a military background and experience in these issues." His five years as a prisoner of war also dramatize the second theme, highlighting his patriotic devotion.

Both of those points are hard for Barack Obama to match. He's never worn the uniform; his father was a Muslim; he had a radical pastor who damned America. Obama's critics paint him as a mystery man who carries profound risks. Voting for him, we are told, would be a dangerous leap of faith.

McCain, by contrast, has gotten where he is because he's a familiar, well-seasoned quantity. He has been in public office for more than three decades, leaving an extensive record. Love him or hate him, we assumed, we knew what we were getting.

The biggest problem with Palin is not that she's inexperienced or has a wayward daughter or recently admitted ignorance of what the vice president does. It's that she's a human torpedo aimed at McCain's strongest attributes.

You don't come across as the prudent option when you propose to put an untested neophyte in line for the most powerful job on earth. Or when you choose a running mate you barely know without investigating her to within an inch of her life. Or when you cheerfully contemplate turning over the nuclear codes to someone with no apparent knowledge of or interest in national security matters. The safe guy suddenly looks like Evel Knievel.

The McCain campaign says it knew about the pregnant daughter before Palin was chosen. But the vetting process was clearly far from exhaustive. Several prominent Alaska politicians, including the one directing an ethics investigation of her, said they never got a call. The senator and his subordinates didn't do everything they could to learn everything they needed to know about Palin.

And what happened to McCain's commitment to his country? By choosing someone so transparently unprepared for the presidency, he indicated he was willing to do anything, including jeopardize American lives, to win the election. If terrorism and the war in Iraq were truly "transcendent" to McCain, as he claims, he would have never considered someone so unacquainted with the topics.

At the rally Friday where the nominee introduced his running mate, the banners said: "Country First." But his actions said something different: "Politics First. Country Second."

Besides helping him with women and the religious right, McCain's selection was supposed to appeal to independents by reminding them how much he loves sticking it to the man. The campaign celebrated Palin as a bold reformer opposed to federal boondoggles and tough enough to buck her own party chieftains in Alaska.

All that may be true, but Palin probably won't enhance his image as a maverick. Choosing a conspicuously underqualified running mate mainly because of her sex was a classic case of pandering. And mavericks don't pander: They do what they think is right and let the chips fall where they may.

That's not what happened here. McCain, by all accounts, wanted either Sen. Joe Lieberman, who was Al Gore's 2000 running mate, or Tom Ridge, the former secretary of Homeland Security — each of whom has the national security props that Palin lacks. But apparently McCain wasn't willing to risk a fight with conservatives over a running mate who favors abortion rights.

Democrats have been trying without success to convince voters that the Republican candidate is not the strong, principled, trustworthy leader he claims to be. Now they can stand back and let McCain make the case for them.

Steve Chapman blogs daily at newsblogs.chicagotribune.com/steve_chapman. To find out more about Steve Chapman, and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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