Nope. The Old Man enlisted because that was what you did. He was there for Australia, not there to be anti Japan who just happened to be the designated foe. Elder Bro was conscripted and correctly decided that he could make a successful career in the military, so he stayed in. Nothing to do with 'good' or 'evil.'I think in the case of Australia and World War 2 it was a different case. If you asked an American why they were fighting in World War 2, or a Frenchmen, they would've told you it was for a 'cause'.
The Civil War and the Confederacy was specifically about slavery and the expansion of slavery in the United States. Some people might not have cared either way and might've enlisted just for the 'excitement' as some people are wont to do, but it was definitely about a cause.
As I said, in the case of Australia and World War 2, it was less about a 'cause' and more about Queen and Country.
On the other hand though, I am surprised by that - World War 2 was definitely a fight of good vs. evil and the Japanese government at the time was evil. Your father and brother were fighting against evil.
If I had been conscripted back in the late 60s, I would have gone in and done what was asked, and it would have had absolutely nothing to do with anything other than........it was what it was......conscripted. No choice.