Do principles matter in the often unprincipled world of politics?

That question was recently put to former Massachusetts governor and Democratic presidential candidate Michael Dukakis by Tavis Smiley and Cornel West. Dukakis was a guest on their PRI show, "Smiley and West," where he discussed the recent Supreme Court decision on the Affordable Care Act and President Obama's first term.

It was an excellent interview. But when Dukakis responded to a question about the Supreme Court's decision in the Citizens United case, the conversation got heated.

Dukakis was asked what he would have done if he was in Obama's shoes: would he reject super PAC money or would he compromise his principles, as Obama did, and get in the game?

Dukakis's answer was a clear message to Democrats: he would do just as Obama has done. Dukakis, like Obama, sharply disagrees with the court's decision. But Dukakis said Obama needs to be able to fend off the super PAC-funded attack ads that are created for one purpose: to destroy the opponent's image.

Obama will be the first sitting president, Dukakis said, who will be outspent on campaign advertising, much of it in the form of potent political attack ads.

The impact of political attack ads is something Dukakis knows a thing or two about. A political action committee working on behalf of George H. W. Bush in 1988 made Dukakis look like Daffy Duck on the issue of violent crime. And Dukakis admits he was slow to respond, taking what he called at the time the "high road."

He has since advised many leading Democratic politicians not to underestimate the power of attack ads, including Senator John Kerry in his race with George W. Bush.

But Smiley and West both cringed at Dukakis's response. Is winning at any cost winning, they asked? And given Obama's stance on the need for campaign finance reform, has he sacrificed his principles to be president?

Democrats, who have been slow to contribute to super PACs, can and should have their dirty-money debate, Dukakis said. But to have a significant impact on policy, you first have to win elections.