[jellicle]

There are plenty of people in jail and dead for the act of sending a check to someone. Giving money to someone is a crime in many circumstances, among them:

http://www.law.cornell.edu/uscode/text/18/2339A

(Computer crimes are covered there; that is to say, anyone providing money to encourage or support anyone performing any sort of computer crime against U.S. national security is themselves guilty of a crime and liable for up to 15 years in prison.)

[declan]

If you read the title at the top of the page at the link you provides, you'll see it's "Providing material support to terrorists." Manning has not been charged with terrorism.

[jellicle]

The subheadings are not part of the law and are there for general information only. If you read the specifics of the law, as I said in my comment just above, the law covers giving money in support of a wide variety of crimes, not just KABOOM! terrorism, despite the title. The wide variety includes computer crimes.