I have a feeling that if one of the major banks fails, it will take a good many more down with it. FDIC will cover some of the losses, but not all.
There has been some discussion about eliminating cash, mostly by people that don't live in the same world with the rest of us.
http://www.bankrate.com/finance/checking/will-cash-become-extinct.aspx
I see Mr. Trump wants to withhold remittances sent to Mexico until they pay for his wall. Good luck with that Mr. Trump. When my mother sent money to family in Mexico, she used to put cash between the pages of a religious magazine and mail it. Sometimes it took a long time to get there, but it always got there. Nobody is interested in someone else's religion.
If she got caught doing that now days, she probably rot in prison.