Should leaders lead on the basis of principle or public opinion?

This thread is aimed at a very fundamental question. Many Republicans constantly refer to President Bush as being a man who governs by "principle". The Democrats like to point out that Bush is, more often than not, governing in manner that is against the will of the people. Yet, every election, candidates are touted on the basis of their principles. Which do people want, a man/woman who governs on the tenets of announced principles or on the basis of public opinion polls? What if one's "principles" clash with the polls? Would people respect someone who stood fast on principle or who could be swayed by public opinion? Can we have it both ways?

Actually, I think a little of both is necessary.

On issues such as Civil Rights, I think there should be no public opinion involved anywhere. It should be a "fair is fair" look at current laws. Do you think rich white land owners would have given their slaves freedom? Or what about the man of the household giving the wifey in the kitchen the right to vote? The gays to marry? The blacks the vote? These issues are far and above the common man. Also, war shouldn't be really swayed by P.O. Nor should legal/illegal drugs be up for that.

But, I do think other things should be up for public opinion. The way we are taxed, for example. Retirement/SS, for example. There are many other things that should be swayed by our opinion. But the main way to do that is to contact your congressman and senator. If enough people disagree, they may actually vote your favor...ideally...