Yes, plain as the nose on your face, as you immediately than acknowledge:
Of course, what idiotic evil monarch would say, "Kill these people, so that I won't have to pay them back." Much better to say to the illiterate masses ignorant of Judaism, "These are wicked Christ killers."
Who provided these monarchs with this cover story? The difference between and excuse and a reason is just point of view.
The church could not act decisively because it had no wish to. The church has issued multiple Papal Encyclicals denigrating jews, heretics, and women. Hitler did not invent forced ghettoization for Jews, yellow arm bands for jews, or employment restrictions for jews; Popes did, by encyclical. Furthermore, jew-hatred is endemic in church theology. It is fundamental to Catholicism that, although remorse and confession, or even simple savage innocence, can remit any other sin, if you know OF jesus, but do not accept his as savior, you are irredeemably damned. This is the Doctrine of Salvation.
If, on the other hand, you are an orthodox jew, it is fundamental to your faith that, because there can be no other Gods before Him (this is a Commandment, it might possibly be covered in your 400 historical works), Jesus is just a good man, and salvation is derived from obedience to the word of God. This is sometimes called the Doctrine of Works, as opposed to the Doctrine of Salvation, and a jew is reminded of it, every day when he says the shema.
This fundamental conflict is the persistent wellspring of officially voiced (and you don't get more official than a Papal Encyclical) denigration of jews coming from the Voice of Peter. Trying to pretend the Church has no culpability in the events we've been discussing, given that the church itself acknowledges its culpability, is remarkably silly, even for a person whose mananaged not to know who is responsible for the Inquisition with his 400 history books.