"On June 4 1963, President John F. Kennedy issued Executive order 11110. This ordered the Treasury to print United States currency backed by the Silver in the vaults of the Treasury they would be non interest bearing, the government would no longer have to borrow Federal Reserve interest bearing money and increase the National Debt. It would have put the Federal Reserve System as we know it out of business. The bills were printed but removed from circulation immediately after Kennedy's assassination November 22, 1963."
If he didn't know, perhaps he suspected enough to make him a liability. As a former PT-109 skipper, how do you think JFK would have responded to the USS Liberty incident?