well there's quite a bit on WW1&2
in WW1, most denominations supported the war. the protestants, cause they wanted to support the home country, england, and the catholics, to show their support, to avoid conflict with the protestants and the people. They felt a need to show their support, after having conflicted with the protestants so much on other issues, and in so doing, created a bad reputation for themselves. It was a way to prove themselves.
in WW2, much the same thing I think. the protestants of course were supporting the home country, and the axis were threatening australia. not sure what the catholics were thinking.
course you've always got the radicals, who were against the wars, and were against conscription, on both sides. the majority of the catholic population were against war in both, but the church itself supported it.
that's all I can remember. i'd better go over it again.