Why were people booing Obama when he said no health insurance for illegal aliens?

First, who was booing him? cus it seemed like the republicans were.... Second, why the HELL would we give health insurance to people who don't even belong in this country in the first place? that is just going to be another incentive to stay in this country illegally...
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The boos weren't for Obama. They were for a boorish Republican in the audience who called Obama a liar when he said the plan wouldn't cover illegal immigrants.
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