"...the Catholic Church has just excommunicated John Kerry" - no it hasn't, and the contents of that link don't actually say that.

It's a partisan spin on a canon lawyer's interpretation of a more general position, and of the applicability of it in a particular case. No Bell, Book and Candle.

The truth is, the Catholic Church is a lot less monolithic than people imagine.

Kerry's position, as I understand it, is that while he believes that abortion is wrong, and that a choice to abort is a wrong choice, the constitutional position in the United States is that there is such a choice, and this should be respected. And that is a position which is perfectly consistent with Catholic teaching.

There's a quote Jim Wallis in an article, tucked away inside that Sojourners link up the thread, which strikes me as relevant here (and don't anyone go pointing out Jim Wallis isn't a Catholic, because I know that):

"I have clearly disagreed with the Democrats on abortion, believing that Christians can be both "progressive and pro-life." I've urged the Democrats to be much more respectful and welcoming of "pro-life Democrats."

"Someday, a smart Democrat will figure out how both pro-choice and pro-life people could join together in concrete measures to dramatically reduce the abortion rate by focusing on teen pregnancy, adoption reform, and real support for low-income women. That would be so much better than both sides just using the issue as a political football and political litmus test during elections, and then doing little about it afterwards."