RUTHFULLY YOURS

Here’s a quiz: For which of the following reasons is the 44th president of the United States bad-mouthing Mitch McConnell, John Boehner, Sarah Palin, Rush Limbaugh, bankers, mine operators, insurers, Glenn Beck, the tea party, the Supreme Court and whoever he hammers as we go to press:

a) He’s rallying his base.

b) He’s rallying the Democrats’ base (one overlaps but does not equal the other).

c) He’s changing the subject from 9% unemployment.

d) To reverse his sinking approval ratings.

e) It’s what Saul Alinsky would do.

f) It’s what Barack Obama likes to do.

Astute readers instantly saw that the answer is, all of the above. (Incidentally, the left’s notion that Mr. Obama had to prove he could “stand up” to the Republicans must be laughable to the man who stood down the Clinton machine to win.)

Republicans such as Mitch McConnell, a target of Obamian invective, are calling it conduct unbecoming a president. They are right. Carter, Reagan, both Bushes and Ford didn’t do it. People assume the hyperpolitical Bill Clinton did it, but if memory serves, his public persona was presidential to a fault, even as he brimmed with Vesuvian anger.

But as Bill Clinton once explained to Bob Dole, in politics today you do what you’ve gotta do. On current course, Barack Obama’s approval rating is heading toward 40% and an almost certain Democratic wipeout in November. The result would be a moribund first term. The Obama White House has seen this movie before. It was called the second Bush term.

Bush 43 famously, and convincingly, said he didn’t care about polls. What got a little weird was that he kept saying this even when in 2007 his approvals plowed toward 30% and the Iraq War raged on. If you walk the halls of Congress now and ask the minority Republicans “Do you miss him yet?”—the answer is: no. Presidential deference killed them in 2008. When Vice President Dick Cheney was finally able to launch a counterattack, it was 2009.

Perhaps uncertain where his own vice president would go with such a killer assignment, Mr. Obama has decided to take down the opposition himself. This may be the Obama version of “you do what you gotta do,” but politics has a brutal truism even bigger than that: Will it work?

Let’s look at the reasons to justify going negative.

• The Obama base. Modern Politics 101: Fail to max out with the base and you lose. The 2008 Obama victory was a miracle of base-raising. Minorities, neophyte voters, labor, wannabe lefties and suburban women voted for Mr. Obama at record levels. The bad news: That victory was rock-star politics, and if you’re the man, then the audience wants more of whatever fire drove them into the arena. In this hot new political world, a mere president may be boring. Crank them up, or lose. Go negative.

• The Democratic base. This is the party’s bedrock: public-sector unions, plaintiffs lawyers, community organizers, the left-wing blogosphere, NGOs, Big Pharma. The fact that their economic interests are yoked forever to Democratic power ensures maximum effort. Do or die. For most of them, go-negative is chromosomal.

• Unemployment. Top 10 reasons why the White House lies awake at night: The economy is reviving but employment is not. Solution: Attack Sarah Palin and Glenn Beck. The White House knows that every day the media is writing or talking about their man’s cat fights with conservative celebrities, it isn’t doing stories about “Depression-like” unemployment. Go negative.

• Presidential approval ratings. At the time of his Inauguration, Mr. Obama’s Gallup approval stood at 69%, the highest since JFK. Today his RealClear Politics Approve/Disapprove aggregate is 48.3/46.0. He’s four points from 50% disapproval, which would be a benchmark of disaster for Democrats in November. Go negative? Maybe not.

There may be any number of good, political reasons for Mr. Obama to let it rip. But let’s cut to the real reason this is happening. The answer is (f): It’s what Barack Obama likes to do.

And it’s a mistake.

Even Achilles had a heel, and Mr. Obama’s may be his decision to be his own Saul Alinsky. Defining, demonizing and making a mockery of one’s opponents was one of Alinsky’s main rules for community organizers. But community organizers, though often charismatic, can also be annoying jerks.

The only Barack Obama the American people have ever known is the one presented to them from January 2007 onward—the amazing, improbable fellow in “Dreams from My Father.” Candidate Obama was about as perfect as it ever gets. The best since JFK.

JFK, an imperfect man, worked hard to stay perfect in public. So did FDR and Bill Clinton and Ronald Reagan. For Barack Obama to believe that any persona he offers the public will be OK with them is hubris. Showing voters a side of him that he enjoys, but many of them may not, is flirting with disaster. If all the positive vibe that held up his presidency on its first day ever breaks, the fall could be fast.

Write to henninger@wsj.com