> which will be required to board a plane soon

Assuming that this time the deadline doesn't get pushed back at the last minute again like has kept happening so far.

Passport will also work

The irony with that is that if someone undocumented wanted to leave the country, this requirement could potentially hinder that.

I also don't really want to have to carry my green card around everywhere. Just one more thing that can be lost.

How would it?

To travel internationally, a passport is required (not drivers licenses).

I might have been being more simplistic than I needed to be, because there are other travel methods, but I was more meaning, "Not everyone lives next door to an international hub" (so might need a connecting domestic flight).

Not 100% required, even for adults.

Those without acceptable identification may complete an identity verification process and face additional screening. https://www.tsa.gov/travel/security-screening/identification

Everyone should experience this at least once - it’s eye opening.

I did it involuntarily because I forgot my wallet once, and decided “well, I’ll either get through and in my way, or I’m too late to drive home anyway and will miss” - and it worked fine.

Even crossed back into the USA without my passport a few times. Just additional screening and bitching is all (at least if you’re a US citizen; membership in the Empire has its perks!).

RealID requirement for domestic flights (still) isn't happening, just like it hasn't happened since it was first announced for requirement in 2008.