It's actually pretty quick in the US, too, despite the bad rap it gets. I have perhaps twice hit 30min security queues at SFO and almost missed my flight, because I like to cut it close and live dangerously.

Typically I arrive about 30-45min before boarding begins and it's no problem whatsoever. I agree most countries I've travelled to have the security lines figured out a lot better in the US, and I just recently got TSA PreCheck so I don't have to take off my shoes and take out my laptop, but it's more about the convenience than the speed.