US President Barack Obama has hit a particular low, with his approval rating sinking below 40 percent for the first time. (Getty Images)

With the president’s approval rating sinking below 40 percent for the first time, this week’s On Leadership roundtable explores Obama’s wavering leadership and how he could steady it—with opinion pieces by former Congressman Mickey Edwards, journalist Evan Thomas, public opinion polling expert Peter Hart, and Harvard Professor Nancy Koehn.

There is an appealing model of presidential leadership where one has low-key, behind the scenes, confident control of the political system. Dwight Eisenhower ran the government that way in the peaceful and prosperous 1950s. And at times, President Obama seems to wish he could lead in the Eisenhower manner. But he can't. The times are different, and Obama is not the same sort of leader as Eisenhower, a war hero whose approval rating averaged well over 60 percent.

Inevitably, perhaps, President Obama has become entangled with Washington politics, caught up in its fractious mud-fighting. He tries to distance himself from the squabbling, but he mostly appears to be vexed and scolding. He needs a way to break free, a way to show that he is a true leader who can transcend beltway-cable TV politics. To be sure, it is hard for incumbent presidents to campaign as reformers—in effect, to stand apart from the government they run. Still, Obama needs to find a way to rise above, and in a credible fashion that promises real change.

That chance to reclaim his leadership credibility? Taxes. Both Republicans and Democrats have begun to call for tax reform that would lower tax rates while raising additional revenue by eliminating tax breaks and loopholes. The plans advanced are all woefully complex, however, and invite endless battles against individual interest groups—the equivalent of political house-to-house combat. Obama needs to cut through the morass and offer a straightforward, easy-to-understand solution with broad popular appeal.

He needs to be truly bold. He needs to return to the 2008 Obama, the visionary of hope and change, to re-invent the crabby lawyer who now occupies the oval office. He can do that in one sweeping appeal: by proposing that we repeal all tax breaks. Every single one.

This is not as radical as it sounds. Economists overwhelmingly agree that broadening the tax base and getting rid of distorting incentives would be good for the economy. It would be an essential step in reducing the crushing federal debt. It could also be popular—for Obama, now languishing in the polls, it could be the key to re-election.

True, some popular tax breaks would have to go. No more deductions for charity or mortgages. But the benefits far outweigh the costs, politically and economically. If you get rid of tax breaks, tax rates can be cut in half. Individuals would have only minimal dealings with the IRS, if any at all. No more nightmare paperwork at tax time.

Tax reform can also open the way for serious deficit reduction. Even if you cut taxes by one-third (still a hefty savings for individuals at tax time), the federal government could raise an extra trillion dollars in ten years. Obama could propose the grand compromise he toyed with this summer: cutting three dollars of federal spending for every extra dollar of revenues. The debt crisis would be essentially solved. The world would regain confidence in the dollar and the engine of American prosperity.

Obama could pose a clear choice: A vote for him would be a vote against the special interests who have a stranglehold on Washington, who carve out loopholes that benefit them but not you. He could propose true change, not just dreamy rhetoric. He'd have to stick with it—no half-heartedness, no split-the-difference, no hedging for campaign contributors. In effect, he'd be betting his presidency by proposing a national referendum. But, by placing himself above the usual partisan wrangling, he could run as president of all the people.

Obama likes to say to his lieutenants, "We were elected to do big things." Here is a way to get re-elected by doing a really big thing.

Evan Thomas, a former editor at Newsweek, is finishing a biography of President Eisenhower.

More from the roundtable:

Mickey Edwards: How well is Obama using his bully pulpit?

Nancy Koehn: Wake up, Obama: Listen to your forefathers

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