When a thief tries to steal a wad of cash from my home safe though, he has the risk of leaving prints/DNA on the scene, getting caught on camera or being spotted by a neighbour.
When a thief tries to steal a wad of cash from my home safe though, he has the risk of leaving prints/DNA on the scene, getting caught on camera or being spotted by a neighbour.
Bank fraud on the other hand is the banks problem. If someone steals your money the bank makes it whole.
With cash the cops would have to raid my apartment to get the money (also likely they wouldn't know about the money in the first place, so no cop raid there!).
So yes, uncle sam can steal the money in your mattress without having access.
Or the Fed could release a newDollar and only accept a certain amount of oldDollars. Russia (I think) has done that once or twice.
2/3 of oldDollar cash is stored outside the US by people who mostly can't enter the USA without visas etc. And those will be pissed royally.
It would be not wise choice to piss off more people than your own population, however not never done by the USA.
"We'll just take the money in your account, because [insert any political excuse, bonus if it contains the word crisis]."
I'm pretty sure it happens a lot that petty theft goes unsolved.