Shalom Hamou

U.S. Treasuries: Not a 'Risk-Free Asset'

Treasury Bond have only interest rate risk which is a systemic undiversifiable risk meaning that it is impossible to diversify away from it.

About Interest rate risk read:

The Risk in Long-Term Interest Rates and Stagflation.
seekingalpha.com/artic...

That said in a Liquidity Trap only Cash and Short Term Assets (Gold and Silver) are King!