I think it can be done ... with positve reinforcment and constantly pushing these issues a massive mass media campagin, advocacy, awarness and such people will start to be more aware they may not change their minds and that wuodl not be the purpose but they could become more tolerant.

To actually get them to change their minds is a whole other ball game I think and is generational as you may suggest.

Within this time frame, I am afraid it is impossible.... Unless one finds out the biological implications of being intolerant. Then may be some kind of a medicine or a vaccine can be devised to do the job.

If this intolerance is caused by social practices (the way we are taught to respond to our needs, to solve our problems, and differences, etc), Then the traditional way of thinking would assume a social vaccine to get rid of that. That, defintely will take a long time. So, may be going to a more fundamental level (Biology) might give us what we need. Of course this might require years of research. But, theoretically, a vaccine might be there.

In practice and theory, some people might get away without the vaccine.So, what will you do to them? Research itself might reveal an antidote to the intolerance vaccine. Other thinkers, groups, etc might question the morality of changing our biology, etc. 

So, as you can see, the answer is still: impossible.

What do you think?