Adding to what Teribus says about the 1812 War, the truth is that the war was very unpopular and Madison's big mistake, which is why he spent two years trying to stop it, as it had almost bankrupted the US Treasury.

And Manifest Destiny sounds much better than stealing land and racial cleansing. I was in the USA this year. Probably the only treaties the US Government have kept are ones that allocated the land the land that the Native Americans own now. And that's basically desert.

You have to accept what previous Governments of any country have done. It's a matter of historical fact. You don't have to stick up for them for national pride. It wasn't us. Some Big Boys did it and ran away.