"The US military hasn't defended America since the War of 1812, genius"
I wouldn't be too quick to call that much of a defence. They started out on the offence, then things kind of went sour from there. But hey! The White House probably needed new paint, anyway.
Five decades later, the Union army, (which I guess you'd have to call the army of the United States, wouldn't you?), defended the Union from break-up.
Even if you discount the Aleutian campaign (as I'm sure you have) it is easy to make the mistake of seperating "America" with America's interests".
Should you take up arms against someone who has invaded your home? It would seem you should, (provided it is indeed your home and you have a right to be there). What if that someone has blocked the road to your home so that you cannot go to work or bring home food or goods? Is that not an attack upon your freedom, upon your life, perhaps?
If we trade, or carry out commerce in the world, placing restrictions upon right of passage or trade can be construed as an attack upon the country which is restricted. Unless your country is entirely self-sufficient and trades with no-one, you are vulnerable to interruption of trade through action outside your borders. After all, most wars are fought for commercial reasons, including the War of Independence and the Civil War.
Let's see. I'm guessing I'll get comments 2, 4 7 & 13.
Les