And if that doesn't work, there is always confiscation.
"CME confirmed silver margins raised from $5000 to $6500 (30%) effective 11/10 settl - no other metals effected"
Presumably, this affects the maintenance margin. And is a lovely way to kill paper longs.... but not shorts, of course.
This is also the last remaining self-regulating way for the market to tell the genocidal lunatic in the Eccles building to go fornicate himself, and his excess liquidity.