How come it seems for the past decades the Catholic Church has been plagued with sex crimes especially among young boys? How long has this been going on? Or did I just miss something up.

The sexual abuse of young boys has been going on for a very, very long time but for most of that time, the church and all its institutions were unassailable and infallible. So most of it went unreported at the time. The attitude that the church and by extension, the priest could do no wrong was especially prevalent here where I grew up. Which is why some truly horrible things were allowed to happen. The church committed some vile acts and they weren't all sexual abuse and enjoyed the protection of the government all the while. Here have some fun reading.