What makes many people think Marines are tougher than the Army?

With all due respect, I keep hearing that Marines are tougher than the Army but I really do believe it’s the person that makes the uniform…not the uniform that makes them. I hear that the Marines are tougher and better because they have three weeks longer basic training, better combat moves and shooting, and more discipline.

I don’t get it really because why does three weeks make a huge difference in whether or not you’re a better soldier? In the Army there is Airborne school (which is tough 3 weeks), Air Assault, SERE training (which is something I can’t imagine lol), and a lot of other things. Also, when it comes to the shooting and fighting, what’s the difference between a Marine expert shooter and an Army expert shooter if you’re shooting with the same rifle?

Please no bashing on either branch, be respectful. I am just here to discuss this like civilized adults…not children. Haha, I know how ugly things like this topic can get.