It was wholly a pleasure to get your pointed question about a phrase I used the other day about those who "tend to confuse ideology with principle."
What's the difference, you asked, and would I know?
You have a point, for one man's ideology can be another's principle. Someone whose politics we don't much like we call an ideologue, while someone we agree with is of course a person of principle. But your point has its limits, for there's a reason one word is usually offered as criticism and the other as praise.
Ideology is a modern term (for ours is an age of ideology), and we even know just where, when and by whom it was first used:
In France in 1796 by one Destutt du Tracy. The concept of ideology is one more unfortunate legacy of the French Revolution. Even though definitions of it may vary, the word has come to mean a set of ideas, usually in politics, that narrows the mind while enflaming the passions. Which is why it has become a term of opprobrium rather than description.
Think of the mobs during the Great Cultural Revolution in China. Armed with their little red books of quotations from Chairman Mao, they set out to destroy an ancient culture. For an example of ideology in even bloodier action, think back to the Khmer Rouge and their killing fields in Cambodia.
Naturally enough, the Frenchman who would coin the word ideology had been imprisoned during the Reign of Terror, a victim of ideology himself. The history of words, like history itself, is just full of delicious if not always pleasant ironies.
By now, only professors may use the term ideology in its original meaning -- as a guiding group of ideas or worldview. In general usage, it's come to mean something more rigid and intolerant.
It is easier to illustrate the difference between ideology and principle than to define it. Just compare the writings of Karl Marx, who spoke proudly of his ideology, to the Federalist Papers, which are blessedly free of it.
By their fruits ye shall know them: Compare the French Revolution, which became the historical template for modern revolutions, with a quite different one -- the American Revolution. One would culminate in a Reign of Terror followed by Napoleon's dictatorship, the other in a republic and the Constitution of the United States.
For an example of ideological rhetoric that enflames the passions while narrowing the mind, it would be hard to find a better example than the campaign waged against the nomination of Robert Bork to the U.S. Supreme Court in 1987. It was so vicious that it gave birth to a new verb in the American language, " to bork," meaning to savage a nominee for office. The prime example of that technique was the speech the late, not altogether great Ted Kennedy delivered on the floor of the Senate within an hour of Judge Bork's nomination -- even before the confirmation hearings had begun:
"Robert Bork's America is a land in which women would be forced into back-alley abortions, blacks would sit at segregated lunch counters, rogue police could break down citizens' doors in midnight raids, schoolchildren could not be taught about evolution, writers and artists would be censored at the whim of government ..." and so hysterically on.
There were sound reasons of principle to oppose (or support) the judge's nomination to the court, but this was just an ideological diatribe.
It's not a pretty sight, ideology in action. Some scenes from American political conventions are hard to forget. Much as I might like to. For example:
There was the Democratic National Convention in Los Angeles back in 2000 that nominated Al Gore for president. It featured marchers endlessly chanting, "They Are the Powerful -- We Are the People!" Whatever words the mobs in Paris chanted as they escorted the nobility to the guillotine, their spirit was much the same.
Or consider the scene at the 1992 GOP convention in Houston after Pat Buchanan delivered a ring-tailed roarer of a speech denouncing all the Enemies of the Republic from liberals to homosexuals (as if one couldn't be both). It was a resounding blow in the Kulturkampf that was dividing the country at the time. In spirit it could have been that of a harangue delivered in a Munich beer hall circa 1923. But the mob -- excuse me, the convention delegates -- ate it up.
That performance of Brother Buchanan's provided a stark contrast with a farewell address delivered during that same convention by an aging but still strikingly handsome and eloquent Ronald Reagan, who radiated good will in every direction as he left the national stage. As he told the delegates, "whatever else history may say about me when I'm gone, I hope it will record that I appealed to your best hopes, not your worst fears, to your confidence rather than your doubts. ... My fondest hope for each one of you -- and especially for the young people here -- is that you will love your country, not for her power or wealth, but for her selflessness and her idealism."
Ronald Reagan's appeal to the better angels of our nature provided the perfect counterpoint to Pat Buchanan's hateful tirade. At that one convention you had the perfect, back-to-back contrast between ideology and principle. One lowers the tone of public discourse; the other raises it.