I travel about once a month to the US and back to Canada... the security lineup can take up to an hour sometimes leaving SFO. So if I don't want to have a chance to miss my flight, I have to arrive 2 hours early really.

did you sign up for tsa precheck and/or clear? If you travel that much the amortized cost would make sense. You basically get inserted into the line right after the "check id" part and don't have to take off shoes/ laptops

To/from Canada might want to look into NEXUS. Slightly more money but you get precheck, and immigration line skip both directions.

I'm assuming this is the international terminal? I fly ATL->SFO every 3 weeks or so and SFO domestic is the fastest airport ever. I'll leave downtown SF at 1 and get to airport, drop my bag off and be at gate in ~30 minutes.

ATL on the other hand....even with TSA pre I can take a full hour.

SFO is the only airport manned by private security instead of TSA, that is the reason it is super efficient.

I've cleared from the entrance through security to my (domestic) gate at SFO twice in ~15 minutes. It really blows my mind how they pull that off.

Better training, more incentives to be passenger focused etc. might be the reasons.

In fact in some contests these private guards performed 5x better than TSA employees in catching the bad guys/bad items while actually doing it lot faster.

For ATL - you can go in through international terminal and take the tram to the domestic gates. There is just less parking on the international side.

Wow, I just flew out of IAD and even though I arrived at 4AM for my 5:15 flight, security still took 45 minutes. The line was already twice as long by the time I got through.

I don't even want to think about trying to get through at a reasonable hour.

Oh, I always arrive early. No reason to take the risk, I can always sit and read a book. But I spend a lot more time waiting than I ever have getting to the gate. It's really just an overabundance of caution.

Many people (including me) consider the imposed waiting at the gate time part of the travel time. Whether from an abundance of caution or rational reaction to the wide variability of security procedures (and ground transport), it's still part of the total trip time.

That's fair. Though I've yet to actually need that time, so I feel arriving at the airport with less than an hour to go is a realistically acceptable thing I could do.