A Chequer-Board of Nights and Days

---Niccolò Machiavelli.

How about that little known third category? You know, the one where the ministers or advisers give good advice and the ruler--or in this case, rulers--just refuse to listen?

YET ANOTHER Democratic adviser is in trouble for having more common sense that his candidate -- or at least, more than his candidate has the courage to admit having.

First there was Austan Goolsbee, Sen. Barack Obama's economic adviser, who suggested to Canadian officials that a President Obama probably wouldn't be foolish enough to repudiate the North American Free Trade Agreement. As Mr. Obama had been running hard against NAFTA, blaming it for a million lost jobs and ignoring the good it has done for the poorer people of Mexico, Mr. Goolsbee's comments had to be repudiated.

Then Mr. Obama's foreign policy adviser, Samantha Power, was forced to resign. Her immediate sin was to call Sen. Hillary Rodham Clinton a "monster," which was undeniably indefensible. But what caused Mr. Obama more trouble in subsequent days was a contemporaneous comment Ms. Power had made to the BBC suggesting that, once elected, Mr. Obama might not be so reckless as to order an immediate withdrawal of troops from Iraq but rather would consider the situation and listen to advice from the military. Mr. Obama did not entirely repudiate this truism; but Ms. Clinton pounced. Ms. Power's comments proved Mr. Obama's promises to be "just words," the Clinton campaign said. "And if you can't trust Senator Obama's words, what's left?" Since Mr. Obama had repeatedly attacked Ms. Clinton as not setting rigid enough withdrawal timetables, her attack was understandable.

Now Ms. Clinton has her own difficulty: One of her top aides, Mark J. Penn, was helping Colombia's government win congressional approval of a U.S.-Colombia free-trade agreement that Ms. Clinton opposes. Mr. Penn was charging Colombia for his advice, and a candidate is entitled to ask that her advisers not accept clients with opposing views. But, of course, the real danger was that Democratic primary voters and unions might question Ms. Clinton's primary-season conversion to anti-trade fervor.

Be sure to read it all and note (again) that Penn's position regarding the Colombian trade deal is the one that is backed up with facts and truth. Clinton and Obama are certainly free to refuse to acknowledge that truth--and the many others--that their advisers have stated on a panoply of issues. But what precisely does that say about the "reality-based" nature of the two Democratic Presidential candidates?