It means Brennan early on showed a contempt for the values of this country. That as head of the CIA, he was sworn to preserve, protect and defend. Supporting Communist Party USA no less, an ideological group as in opposition to our Constitutional/ capitalist government as you can get.
That he similarly is now part of a revolution to displace our Constitution in a Deep State coup against Trump, to seize power by any means available. By any abuse of power.