yeah no shit, america is a melting pot and it’s food culture is an amalgamation of foods from other cultures

And frankly some aspects of most of those are spurious. The origin of the hamburger is debatable mainly because before america it was (probably) just a mince patty served with sauce, much closer to what japan serves as hambagu/ハンバーグ. It likely wasn’t until it came through shipping ports to america that it was served on bread, ground instead of minced (though this was likely a function of the era), and eventually over time evolved to the modern version of what we consider a “hamburger”

Mac and cheese actually goes back to medieval england and was closer to a lasagna. The extruded version is also probably england, or possibly france. Unless you’re simply attributing dried pasta, which is probably an italian invention, but may be arabic

Frankfurter is german but the modern hotdog is american and debatably the idea of serving it in a bun is an american invention, which again goes back to the hamburger and the insanity of prior to america people struggle to combine meat and bread

In closing I bet you’re fun at parties. Also while america sucks at so many things we definitely make the best burgers in the world, hands down