> Fort Knox has an entire military base to secure it

Fort Knox has basically nothing to do with the modern U.S. dollar financial system.

You don't consider a country's reserve assets to be a factor in their monetary system? An interesting way to see the world.

> You don't consider a country's reserve assets to be a factor in their monetary system?

The U.S. dollar isn't backed by gold. The total value of the gold at Fort Knox, about $100 billion, is negligible [1] and does not appear on the Federal Reserve's balance sheet [2]. It is mostly an anachronism from the eras of the gold standard.

[1] https://en.wikipedia.org/wiki/United_States_Bullion_Deposito...

[2] https://www.federalreserve.gov/monetarypolicy/bst_fedsbalanc...

These have to do with storing something of value, they aren't inherent to gold. People are already storing Bitcoin keys in physical vaults: https://www.bloomberg.com/news/articles/2018-05-09/bunkers-f...

The global financial system is interconnected. Fast transactions can happen because counter party risk is removed by a government backstop. In effect you can't have Visa without a "risk free" store of value. Vaults such as Fort Knox are a part of that system.

In the case of bitcoin they aren't inherently necessary to the function of the system, although with the risk of hacks you can make the case for them.