Even I, just a plain parish priest, have had that experience, shaking hands with whoever comes to Mass, many of them total strangers whose personal histories, special interests, and ideological causes I cannot possible know. If someone were to take a picture of me shaking hands with such a stranger, would it mean my endorsement of something that stranger stands for? In fact, sometimes a stranger does try to pull me into a conversation endorsing something I don't agree with. My usual course is to say something bland and change the subject, politely signifying my unwillingness to go in the direction he or she is trying to take me.
It is hard to know exactly what was going on when Pope Francis had his now famous meeting with Kim Davis at the Holy See's Washington nunciature last month. The Pope was gracious and welcoming, as he is wont to be - as any pastor ought to try to be. He was probably told something about her, but exactly how much he knew or understood about what the Holy See now calls "her position " is unclear, to say the least.
Perhaps he was told that she was someone who had spoken out publicly in defense of marriage, which is certainly true. Perhaps he was even told that she was a fighter for religious liberty who was jailed for following her conscience, which is false or, at least incompletely true. (She was jailed for not only not doing the $80,000 job which she was elected to do but refuses either to do or to resign from, but also for preventing her deputies from fulfilling her job's duties in her place - in other words, not just for conscientiously following her own religion but for forcing her religion on others.)
Even if the Pope knew her whole story, which seems highly unlikely, what was the Pope supposed to do? He said some friendly, encouraging words and gave her a rosary. Popes talk with powerful people with whom they do not necessarily completely agree all the time (including obviously on this trip to the US, indeed every day of that trip). Shouldn't he extend the same courtesy to someone who is not so powerful?
By the way, don't we all do that? Or, if we don't, shouldn't we? When Supreme Court Justice Samuel Alito attended Mass in my church, I made a point of going up to him to greet him and welcome him - out of normal human politeness and sincere respect for his exalted office. That most certainly didn't mean to suggest that I necessarily agree with or endorse anything he has ever said or done as a lawyer or as a justice.
Or are good manners only for friends, and "mercy" only for the "politically correct"?
And if you salute only your brethren, what more are you doing than others? Do not even the Gentiles do the same? (Matthew 5:47).
The more pressing question, of course, is who invited her and why? Obviously someone with the right connections at the nunciature saw an opportunity - like the person who slipped the Chinese flag into Paulson's son's hand in the movie.