Bigotry must be learned. Children are not born with it.
That is a misleading half-truth.
Prejudice may be learned--but it's much easier to learn than tolerance.
Tolerance is a virtue--and like any other virtue, it's difficult to acquire, and easy to lose.
Source?
You can't be serious.
All the latest research into the sources of prejudice indicates that it's a natural and instrumental response to some of the fundamental problems of human existence. Which is why it has been nearly universal throughout history.
Terror-management theorists, for example, argue that prejudice is rooted in our awareness of our own mortality. While subjective uncertainty reduction theorists argue that prejudice is rooted in our attempts to reduce the uncertainty of existence. Ervin Staub anticipated these theories in his book
The Roots of Evil, where he argued that prejudice was a psychological coping mechanism, and a natural response to the ordinary difficulties of life.
Thus, to say that 'bigotry must be learned' is like saying 'being human must be learned.' If children aren't bigoted, it's because their needs are taken care of by their parents, and because they don't understand yet that their own death is inevitable.
What's more: social-psychological research has shown that prejudiced attitudes and behaviours can be picked up at the drop of a hat. Our attitudes toward other people, and our behaviour toward them, are powerfully shaped by our social role, and the perspective which this role imposes. Only the strongest personalities are able to resist its influence.
For examples of this effect, see Philip Zimbardo's work, beginning with the Stanford Prison Experiment; or Christopher Browning's research into the Nazi-German Order Police in Poland; or the work of Huggins and Haritos-Fatouros on police torturers and death squads in Brazil, under the military dictatorship.
Finally, history is replete with examples of formerly tolerant societies becoming savagely intolerant--sometimes practically overnight.
To use just the most obvious example--anti-semitism--prejudice against Jews has waxed and waned throughout European history. European Jews made remarkable advances toward political and social equality in the early 19th-century, only to suffer a backlash in the latter part of the century. Zionism, in fact, arose in response to this backlash, and the hopes that it disappointed: Theodor Herzl, for example, was a thoroughly German Jew who embraced the cause of a Jewish state in response to the rise of explicitly anti-semitic political parties in his Austrian homeland, and to the concurrent upsurge of anti-semitism in France. And in Germany, Jews had been emancipated since 1848, and were well on their way toward achieving full equality when the triple disaster of the Great War, the Great Depression, and the rise of the Nazi Movement struck.
Frankly, your position flies, not just in the face of expert opinion, but of simple common sense.
So: where's
your source?