The position is this: The Constitution guarentees the right to build the community center, but we shouldn't do it, because it is offensive to the victims of 9/11. Some people have argued that the community center should be built because it is a right under the constitution. This argument is a circular argument, although I think its based on the implicit notion that freedom of religion is a principle, not just a right. This is ultimately correct, and should be made more explicit. It's all fine and good that the government is not supposed to be able to deny this right, but if people who are not the government can trample on your freedom of religion, you don't really have that freedom at all. The same applies for speech and anything else, provided we actually buy the principle.
There is however, an even more absurd principle being advanced by opponents of the community center. Just as freedom of religion is a principle, so, we are being told, is the principle that no one should be offended. While not offending people is undoubtably a good principle for getting along with other people, it is downright immoral as a political principle.
Justice offends people who oppose it. The racist will always be offended by racial equality. Sexists are offended by feminism. This is logical and obvious. No one would argue that the civil rights movement was wrong because it hurt the feelings of the Ku Klux Klan.
Likewise, I'm sure Muslims are offended by the notion that this community center is offensive. They should be. To suggest that a religious group that consists of 1 billion people represents terrorism or 9/11 in some way is a statement of discrimination against that group.
Not all offense is created equal. To pretend that bigots deserve the same respect for their feelings that people who are being discriminated against do puts all logic on its head. If you find the notion of equality offensive, than you deserve to be offended.