Not having flown since the seventies, when I was in the Army, I was a bit apprehensive about flying to Argentina (MSP-DFW-SCL-COR) in 2011. But I did my homework, booked directly with AA (codeshare with LAN), single ticket, and read up on 3-1-1 bags and how to pack a laptop as carry-on. I got stressy when my fight out of MSP was delayed by a mechanical issue -- eventually seven hours -- but the AA guy at the gate spent an hour finding me a new way to Argentina, via DFW-LAX-LIM-SCL-COR. While passengers waited to get out of MSP we were given soda pop, juice, fruit, chips, granola bars, etc. I later ended up spending several hours in DFW and was offered a hotel voucher and meal vouchers. And I later had to find my way through LAX (changing from domestic to int'l) as a newbie, but the airport people were very helpful, and the LAN senorita that printed my boarding pass at the ticket counter later sought me out at the gate and offered me an exit row seat. I got to Argentina a day late, but got to see how active an airport can be in Lima at 3 AM, with stores open and musicians playing. The return trip went smoothly.
Last summer I flew to Mexico -- MSP-DFW-BJX -- and back, on AA and my only heart-stopping moment was when my name was on the "come see us" list at the gate in MSP. I was happy to learn that my traveling companion and I had, for some reason, been upgraded to First class. All flights were on time, or early.
I never met a gruff TSA/security/customs/immigration person in LAX, MSP, DFW, Peru, Chile, Mexico, or Argentina. It was all please/por favor, sir/senor, enjoy your trip/buen viaje, and thank you/gracias.
All things considered, I think the "system" did a decent job of transporting me several thousand miles, even though I have friends that tell me my trip to Argentina was a "trip from h-ll" and one should fly only if one "wants to be treated like cattle."