Politics and abortion

Since we, in the Catholic Church, see abortion as murder, and wrong, why does the President, Vice President, and head of the House of Representatives all very vocally support abortion with minimal objection from the Church? Yes, we may hear it mentioned from the pulpit in passing, or at one sermon a year, not only is there not much public comment by the Church but Nancy Pelosi even received communion at the pope's mass in Rome. It's no wonder that many Catholics support abortion. They are confused or uncertain where the church stands on this.