What's the Difference Between Abortion, Communism, and Racial Prejudice?

I would suggest that the difference is that abortion is worse than the other two. At the very least, I'd figure them to be equally bad.

Here's the weird part, though. Excommunicating communists is something the Church has a long habit of doing. Blessed John XXIII actually signed off on the automatic excoms of anyone who voted for communists or joined the communist party.

I'm from Louisiana. Most folks here know about the actions of Archbishop Rummel of New Orleans, who threatened the excommunication of segregationists. He wasn't the only guy who did this.

I haven't found anyone who thinks that the latter act was bad. I've found only a couple (literally) who have any reservations about the former. Yet many of these same people would widely denounce any such sanction against pro-abortion politicians. The reasons for this inconsistency are varied, but suffice to say, I find them rather dishonest. I'll go into detail if folks are interested enough in the topic.

If this is such a serious moral issue, which the Church teaches that it is, how can the penalties handed out for similar issues somehow prohibited?