As I said below, one of the dangers of having all these so-called "pro-choice Catholic" legislators run around working to promote and support and fund abortion (and contraception, N.B.) while still calling themselves Catholic, attending Mass, and receiving the Eucharist with the appearance given by some Catholic leaders that this is just fine is that those who are not Catholic, especially our separated brethren in various Protestant churches, are left with the impression that the Catholic hierarchy doesn't really take the issue of abortion all that seriously.
I firmly believe that nothing could be further from the truth; we have seen more bishops in the recent past speak out against abortion, join protesters at abortion clinics and lead prayers there, and otherwise provide witness to the truth that every abortion kills an innocent human being than we have for many years prior to the recent past. So I don't think the lack of episcopal action is always and everywhere proof of a lack of episcopal vertebrae, despite the temptation to believe that on occasion about specific prelates.
I don't know, but I suspect, that one thing which makes some bishops reluctant to force some kind of Eucharistic showdown with dissenting Catholic legislators and other public figures is the negative publicity that would probably result, and the harm that this might do to non-Catholics and their view of the Church--indeed, it might even create a backlash where people would threaten the Church for having dared to "interfere in politics," even though the interference would have nothing to do with politics aside from fostering the radical and controversial belief that even politicians have souls. No bishop, or priest, or other minister of Holy Communion, ordinary or otherwise, wants, I think, to create a situation where network news media personnel are camped out at Mass hoping to see a senator or congressperson given the smackdown at the communion rail (or in line, more often these days), yet in this day and age of cell phone cameras and YouTube videos such an act would be an instant media sensation.
But the reality is that the spectacle of the abortion-supporting Catholic politician attending Mass and receiving Communion is going to be an equally explosive matter for the Church to handle, and sooner or later someone will capture on a cell phone or other small camera Biden or another abortion-supporting politician receiving Holy Communion. News reports are already slipping in the fact that he went to Mass and received Communion this weekend, and it's only a matter of time before some kind of an incident takes place which will require explanation and clarification by the American hierarchy.
Rather than let things get that far, I think the Catholic faithful ought to ask some questions of our bishops. Why is someone's decades-long support for and aid to the "cause" of legalized abortion on demand not considered obstinate persistence in manifest grave sin as described in Canon 915? Are the Church's teachings on abortion and contraception really all that serious, constituting grave matter, or is one's acceptance or rejection of those teachings immaterial to one's self-identification as a Catholic? If the Church means what she says in regard to abortion being a matter of intrinsic evil, how do we explain the reluctance of the bishops to bar those cooperating seriously by their actions with that evil from the reception of Holy Communion (or, indeed, any of the Sacraments of the living?). Is it not true to say, and indeed to insist, that it is not possible to be "pro-choice" and Catholic?
I hope that our bishops will seize this opportunity to clarify these and other related matters. Not only is it important for the sake of Catholics, but for our friends in Protestant churches who are wondering why someone like Joe Biden can keep receiving the Eucharist with no problem despite his support for abortion on demand.