What happens if your American passport expires, can you fly on whatever foreign one you have only? As long as you don't fly to the US. US citizens need a valid

What happens if your American passport expires, can you fly on whatever foreign one you have only? As long as you don't fly to the US. US citizens need a valid US passport to enter the US, even if they also have another passport[1]. Entering the US is literally the only thing I use my US passport for and the only reason I get it renewed. [1] I guess you can try to lie on your visa/ESTA application and hope they don't notice, but I wouldn't recommend it.