I feel that Senator Santorum chose the appropriate verb "exacerbated."
That is to say, President Obama unwittingly caused unpleasantness between the current majority ethnicity and one of our major minorities. It was NOT his goal to do so.
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I think that it may have started when President Obama invited (with the best of intentions) a college professor and a police officer to the White House to discuss their disagreements.
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For me, I was especially dismayed when President Obama decided to bow to pressure from the activists and to discuss the case of the young man who was fatally shot in Florida. When President Obama said something to the effect that if he had had a son, his son would have looked like that young Floridian, President Obama seemed to be taking the side of those people who felt that the young Floridian had been unjustly shot.
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Furthermore, I am disappointed that President Obama's first Attorney General was a very angry gentleman.