You could say he is teaching us what a terrible Pope looks like.
The same can be said for one who kisses the Koran or stands in a line to give the impression that the Pope is just another religious leader among a group of religious leaders in the world.
What's really ironic, is that without ecumenism, salvation would have been reserved only for the Jews...
So ya may wanna take up the "ecumenism is evil" argument with Christ Himself, beacuse it started when He cured the Syriac....
And you can say that Peter was teaching us what an insensitive boar he could be at times. It wasn't a matter of faith, it was a personal choice he made.
It's a lot like people screaming because Pope John Paul II had an audience with Tariq Aziz, as if that was a reflection on the validity of the Catholic faith. It was a personal choice, not a matter of faith, and therefore subject to scrutiny.