Thursday's Wall Street Journal has an enlightening editorial on American economic history -- history that Democrats would do well to learn before they repeat it.

To hear Mr. Schumer and his fellow-traveling columnists tell it, Hoover's great policy blunder was to do nothing, all the while insisting that everything was fine. But the problem with Hoover's economic policy isn't that it was passive but that it was actively destructive.

In 1930, he signed the Smoot-Hawley Tariff Act, setting off a wave of protectionist retaliation that undid the globalization of the preceding decades and did far more harm to the world economy than the stock-market crash ever did. Two years later, amid a bad recession, he undid the Calvin Coolidge-Andrew Mellon tax cuts, raising the top marginal income-tax rate to 63% from 25%. The recession became a Depression.

Now, since we're talking Hoover, which Presidential candidate has a similar agenda of protectionism and tax increases? Hmmm.

Oh, that's right. Just the other day, one of the candidates for President was saying she'd withdraw from Nafta if the Mexicans didn't do what she demanded, and she wants "a pause" in free trade. She also wants to repeal the Bush tax cuts, more than doubling the rate on dividends back to 39.6% from 15%.

Her Democratic opponent agrees with her, except that he'd raise taxes even more, including by eliminating the $102,000 cap on income subject to the 6.2% payroll tax (12.4% when you include employers), and raising the capital gains tax to at least 25%, and maybe even 28%, from 15%. Add up all of Barack Obama's tax increases and his proposals would get entirely too close to Hoover's top marginal rate of 63%.

Ronald Reagan was right, the scariest phrase in the English language is "I'm from the government and I'm here to help."