I don't like this no true scotsman crap with Christianity. If you think Israelis went from oppressed to oppressor in record time, Ima introduce you to this Constantine dude who flipped the script in an afternoon. Because Jesus did what? Helped him in battle.
From that day forward, militant, violent, and expansionist Christianity was the norm. All that crap about the poor is just the "slave morality" that's naturally shed once on has power. They didn't betray Jesus, they upgraded him to a god of war.
I mean...I feel like "upgrading" Jesus to a god of war IS betraying him. Certainly betrays everything he actually stood for. (Or at least that the character of Jesus in the Bible stood for. Not sure there's any real evidence Jesus ever actually existed)
Edit: good = god
Some dude named Yeshua Ben Yosef was drinking wine and saying crazy apocalyptic shit in the first century and got a whole religion. I do the same and I get asked to leave a taco establishment at 3am.
To be specific about it, the same level of evidence used to say Socrates existed or Spartacus existed also says Jesus existed. You could argue the bar should be higher, but if you did that it'd have to be equal for everyone else. It doesn't take raising the bar much before history amounts to just a couple of kings.