I think it’s not generally recognized that the reason Christian nations are involved in a lot of wars has a lot to do with the structure of the Bible.
In the New Testament, Jesus lays out a program that reaches out to all peoples of the earth, as potentially God’s children. This immediately obsoletes the Hebrew tendency to feel as a chosen people they had first dibs on any land near their current holdings.
It obsoletes the superiority of the Jewish people, levels the playing field.
Then Paul spends his career spreading this program. This is part 2 of the NT.
Part 3 of the NT is missing. This would be a history of a Christian nation, which would employ Christian values in foreign relations. It would use war as a last resort, for self-defense. And it would treat defeated enemies graciously. No gratuitous slaughter, or holocausts.
Because part 3 is missing, Christian get their nation to nation relationships from the Old Testament by default, which is as violent a document as you can find anywhere on Planet earth.
I would add that under Douglas MacArthur, second world war, you can find a man who employed Christian principles in administering the occupation of Japan, and he did an extraordinary job.
Had some political hack had the job, the Japanese occupation might have turned into something difficult. Maybe not as bad as Iraq, but not good. He insisted on his soldiers treating the Japanese and their women respectfully. Many Japanese feared the American Invasion because they knew what their own soldiers would have done had they conquered America.
It is recorded in Japanese newspapers of the day, that the Japanese were humbled by the high road the Americans had taken every bit as much as the military defeat itself…
The actions of MacArthur were the actions of one enlightened man.
The U.S. is therefore schizophrenic, with some Christian values expressed imperfectly inwardly, and OT Hebrew militarism expressed outwardly.
MacArthur kept the Emperor of Japan safe, and wisely employed his help to stabilize the Japanese nation, unlike in Iraq today where American soldiers are taught to disparage all of Iraq religion and culture.
Vast difference in wisdom and outcomes…