Americans have depleted their excess savings and are now depleting their credit lines as well. The percentage with delinquent credit card debt is approaching the peak at the end of the dotcom bubble.
"On the horn" meaning "call on the phone" is in my head because the other day I watched Buckaroo Banzai (a 1984 movie) and the Secretary of State uses it to dress down security guards who won't let him pass in a "Don't you know who I am?" moment.
I don't think I have ever heard it in real life - only tv and the movies. My favorite example is from ~40 years ago. In WarGames a general is fond of chewing tobacco and runs NORAD. The defcon setting has just been changed to 4 (or 3?) and he says "Get me the president on the horn." What could be more American than all of that?