Zerocash has a GCHQ/Israel/NSA backdoor.
It's not true. Zerocash will be open-source project which mean everyone can analyze its source code. No backdoor can be hidden.
Also Zerocash dev team appear to be "anti-NSA" people on their twitter.
They intend to keep it closed source according to twitter.
I would suggest you to learn more about a coin before bashing it. This page say different:
http://zerocash-project.org/q_and_aTo facilitate this, Zerocash will be released as open-source software.
Prior to Zerocash, their Zerocoin project is already an open-source project.