

Well it is actually true that an integral part of Christianity itself is the imperative to spread or proselytizing. It is baked into the religion itself. Originally this was an idea to convert all Jews to the new religion, but it was Saul of Tarsus, or the Apostle Paul, who introduced the idea that this should apply to all peoples, not just Jews.
In the words of the Bible itself: Matthew 28:19–20: “Go therefore and make disciples of all nations, baptizing them… teaching them to observe all that I have commanded you.” Mark 16:15: “Go into all the world and proclaim the gospel to the whole creation.”
So while you may be correct that there is a psychologal aspect to it as well, it is also true that it is simply a part of their religion. They are taught that they should do this. It is generally seen as a holy duty to convert others and save their souls.

Are you serious? Do you think 3rd party voters are “centrist”? What third parties are you looking at? 3rd parties are on the ends of the overton window in the US not the middle. If the Democrats ran a centrist to court 3rd party voters then it makes sense they lost. Because apparently they’re morons.