"...a tune that was very similar to God Save the King/Queen, yet the words we chose describe a battle against Britain.

I think you're getting your anthems mixed up there. "My Country to of thee" doesn't describe any battle, and the "Star Spangled Banner" bears remarkably little resemblance to "Go Save the Queen".

What's wrong with it being a drinking song, kendall? Maybe if Americans had a few jars before singing it, they'd find it a bit easier. The trick with drinking songs is, if you can't reach a note, going up or down, find a harmony instead. There's always going to be one or two within your vocal range. That's how harmony singing was invented.