I can't remember who said it, but about a year ago, a former female member of BJ Clinton's administration (not a top person, but up there) said that if we have a total collapse, the US Govt will just do what FDR did in 1933.
Make ownership of gold illegal. Impose a 10 year prison term (mandatory) for noncompliance. Impose a US only "buy back" price that the Govt sets. After gold is turned in en mass, tell the country the price is back to what the world says it is. Tax the hell out of any gains (anyone) made before the US confiscated it, and impose a 10 year prison sentence for anyone trying to avoid it.
Remember, this does not even HAVE TO PASS CONGRESS! The last time it was done, it was an "Executive Order." Now, Obama wouldn't do THAT, would he?
In 1933 (when FDR and the Fed stole everyone's gold), they paid something like $25 an ounce, and then once they had what people were going to give up raised the price artificially to something like $35 an ounce. Not sure how they get away with this today, but I guess anything is possible in the middle of food riots, hyperinflation, Martial Law, and a police state.
Any gold (or possibly silver) that you own in a safe deposit box is not safe (she said this). The Govt can force the banks to open them all up and turn it in with a "receipt" to you. Any gold or silver you have in basement safe would automatically make you a 10 year felon. Think about that for a second. Any gold or silver "paper" ownership you own would be almost worthless.