the ability or willingness to tolerate something, in particular the existence of opinions or behavior that one does not necessarily agree with.
Tolerance used to denote sufferance of the improper or eccentric as in a failure to prohibit, (owing to its origin from late Middle English, the action of bearing hardship, or the ability to bear pain); it has now taken on a connotation of acceptance or even agreement. Popular messages instruct us to "celebrate" our differences.
Once tolerance was seen as a necessary ingredient to the melting-pot society that was America; it has now been elevated to one of the highest virtues in our culture. Examine the words used as antonyms of tolerance: no longer is the intolerant person considered rigid, narrow-minded and nationalistic; he is now regarded as bigoted, hateful and...evil. On the other hand, to be tolerant is to be inclusive, compassionate, and pure of heart.
Tolerance, as defined in the dictionary quotation in the header, was indispensable to American democracy. It allowed voices of dissent--even though they were outre and extremist--while at the same time validating the idea of the normal; it allowed society to hold--and declare--convictions of moral truth without the condemnation of those statements as "hate speech."
With the redefinition of tolerance, those who would have been considered tolerant under the former definition--allowing the voice of dissent while sternly disagreeing with it--are now seen, by reason of the very act of disagreement, or statement of moral certainty, to be intolerant and therefore bigoted, hateful, and...evil.
A curious derivative of this state of affairs is the reverence given to sensitivity nowadays. To be insensitive is no longer a mild faux pas -- it is the gravest offense to the soul of virtue and a social crime so egregious that it often warrants court-mandated re-education in the form of "sensitivity training." Many, these days, seem to measure their own goodness by the yardstick of their sensitivity alone. President Clinton said, "I feel your pain," and people wept at his nobility. Action is optional, but feeling is essential.
The lesson here is not that our culture is transforming to one without morality, but rather to one with a drastically different morality. Thousands of years of Western thought, informed by Judeo-Christian ethics, are being discarded and replaced--in the span of less than one generation--for an ad hoc system based on I'm okay, you're okay sentimentality. And anyone who doesn't hold with this sentiment is deemed NOT okay.