There is a meme going around (again) that, inter alia, "the Federal Reserve
is missing $9 trillion." (See the graphic below.)
I agree with the overall intent of the meme but that claim that "the Federal Reserve is missing $9 trillion" is flat out wrong. 
The idea comes from the fact that awhile ago the Fed had $9 trillion listed as "off balance sheet."
Off-balance sheet does not mean "missing" or "hidden" or "we’re trying to trick you."
It is a standard accounting concept, it is how uncertain assets and liabilities are reported since, because of their uncertain, contingent nature it is inappropriate (in fact, it could be misleading) to include them on a balance sheet.
Off-balance sheet items are reported, just not on a balance sheet - nothing is missing, nothing is being hidden.
A balance sheet basically reports "This is how much I'm worth today."
I own a Mega millions ticket which is sitting on my desk from the day someone won over $300 million. I haven't checked it yet.
That is a contingent asset - contingent on the right numbers being on it.
Should I record that $300 million plus on my balance sheet? Tell the world I'm worth over $300 million?
Or should I report is as a wholly uncertain long shot. As something else, not as a fixed asset or liability. Off my balance sheet.
So, no, the Fed is not missing $9 trillion and it is not trying to trick us.
And yes, there are real problems with the Fed. Libertarian Alan Greenspan changed its fundamental nature as guardian of our banking system.
The Fed did a great job of protecting our banking system for decades, until Greenspan worked his libertarian magic.
We should not do away with the Fed - we should restore it - IOW, "Make the Fed Great Again!" ;)