Of course, every time a Catholic reads the words Kingdom in the Bible they think of the RCC. Cept those troublesome times that it doesn't really fit a church. Like when Jesus cast out demons and said that was evidence of the presence of the Kingdom (interested how y'all can twist that one to fit Kingdom=Church). Jesus also said that it is easier for a camel to go through the eye of a needle than for a rich man to enter the Kingdom of God. Now, I may be wrong, but I don't think there's many Catholic churches turning away millionaires. ;-) Finally, as Jesus was leaving Galilee for the last time, he sent 70 disciples to preach. He told them, "Heal the sick in it and say to them, 'The kingdom of God has come to you.'" Luke 10:9 Doesn't sound like the church to me :-)
Scripture is a large part of our connection with Jesus in the natural world and permits an individual to harbor the seeds of the Kingdom in his heart. The Catholic Church,anchored in scripture,Traditions and the Magisterium is a large part of our connection with the Kingdom of God in Heaven,or the supernatural world as well and permits a society to harbor the seeds of the Kingdom in their collective heart.
I do believe the Catholic Church is the Bride of Christ and He will protect it from error. However,men are imperfect so frequently,imperfect men have transgressed and participated in actions that were evil,that is why the Pope apologised. I think he was trying to send a message to all men to examine their own actions,both as individuals and as members of other systems,organizations and nations.Maybe some did,who knows?