dear King Solomon...
you said: "Jesus completely believed in and endorsed ALL principles found in the Torah"...try and convince a liberal christian half of that
I think that the bible has eluded to the reason behind the need for war. God didn't want to have His people completely corrupted by foreign practices in that He wanted to bring His Son into the world at a later date and be able to "show" in real time how His mission of sacrifice and forgiveness of sins was a reality of that which was foreshadowed in the law and sacrificial system. it is a given that if you want something to remain you have to take measure to preserve it...those are the measures that God took to preserve His "message" from generation to generation.
the fact that there is slavery in the bible and Jesus didn't speak against it seems to be a big problem with those who denounce the notion of God...the fact is that slavery was acceptable in most nations up until a couple of hundred years ago...the point is that the old testament laws might have had a more benevolent spirit towards slaves than the surrounding nations...and Jesus might have taught the church that they ought to continue the practice of benevolence as all, slave and free were actually equal in Gods eyes. this teaching WAS in opposition to the practice of the day where slaves, women and children were accounted as property with little worth...(I've read that one thing that brought the ire of the romans toward the christians is their practice of bringing home or adopting babies that had been left to die by the road or in a field because they were unwanted)...(So, if you can find information about other nations practices in order to compare them then you might not be so quick to judge israel...as their reasons are not ones that would be considered cultural and or personal ambition but "religious"...an expression of the Holiness of God so to speak)
Jesus commissioned His followers to preach all that He had taught them which does include the tenents of the faith which come from judaism...He did not tell His followers to learn and have an answer for every question that arises from the study of ancient texts...He did, however, set aside teachers who have made it their lifes work to study and have an answer or explaination for the questions that arise.
love michelle