Okay, get over it. It's art. It did what it was supposed to like Eben pointed out. Just as the artist had a right to say what he did in that work and you have the right to express yours in your opinion of it, it shows the beauty of the Constitution and both your rights and his to express himself are upheld for all to see. Free speech, free expression by both. What could be better than this?
Once again, thank God we live in a country where you both can do this without ( we hope) retribution.