It is by some means an international sport in that it is played in different countries by people from all over North America.
People underestimate the popularity of football in Canada. I don't think that any sport anywhere in the world is as popular as hockey is in Canada, but putting that aside football is extremely popular there. On par with any other major professional sport in the US.
I think that you're right that football will never be really big in Europe. They just don't produce athletes with the same combination of strength and speed and mental toughness that we do here. Plus I'd never trust a European quarterback because the position just requires too much mental agility and grace under pressure for the Europeans. They're all about see the ball/kick the ball.
What the...? Rugby is far tougher than American football, no big helmets and shoulder pads and shit like that, I mean if you're gonna tackle each other to death do it like a man and don't hide behind protection
Mental toughness? have you seen Spain's athletes as a norm? starting with our tennis players?
Typical American-I'm-The-Center-Of-The-World mentality, anything that you don't do well or isn't popular in your country is not worth watching
And why do you think NFL failed in Europe? American football is as non-international as it can get.