There are entire essays to be written on the 3 subjects you listed in relation to actual Church catechises throughout the centuries and what was actually practised, not fitting for a limited comment section. Suffice it to say, that based on what I know the subjects are more complex, kind of the crusades were more complex than mere imperialism. 

Rather I think it is more poignant to address your own beliefs. In your mind the Catholic religion is not credible in regards to its claims to an objective truth correct? Then as I asked before, why bother with an obviously deceitful religion. If the Church cannot teach in truth than what worth does any of its teachings have?