Thanks for your thoughtful response, Michael. I know travel has an immense environmental footprint, as I acknowledged in my original essay. Yet I'm unwilling to restrict myself from only going as far as my own two feet can carry me.
To me, expecting a spartan, off-the-grid existence is unreasonable. I think we need to ask all privileged people to moderate their behaviors. Instead of insisting that 0 flights per year is the only standard, I think asking privileged people to limit their impact by choosing one international flight per year (or maybe 2-3 shorter-range domestic flights) is more reasonable.
I also wasn't sure why you pointed out that first-class international airfare emits more emissions than most people emit during an entire year. Having never flown first-class, I don't know what would make that ticket emit more emissions than an economy passenger on the same plane. The fancy food they get to eat?
I drive a hybrid electric car but prior to that drove my gas-guzzlers for 10-13 years (selling them when the cost and frequency of repairs started to get annoying). I sincerely hope my current hybrid electric car lasts for 10+ years but it may be that I choose to replace it with an all-electric vehicle once the need for repairs increase. I'm not the kind of person who buys new cars/appliances every 5 years. We use them until they no longer work and/or become too expensive to frequently repair.
I also want to point out that I haven't spent my life going on annual international trips and didn't go on many flights at all for maybe 35 of the 45 years I've been alive. Yes, I am a privileged person/American to have even experienced domestic flights and some international flights. Yes, there are environmental costs. Yet I think the target should be to think carefully about ALL our decisions and not just demonize the person who chooses to take one international trip per year.