I don't disagree with the list. But I do think that few political organizations are going to have the will and discipline to enforce it upon their members particularly in the US. For a political organization with the will and discipline to enforce such practices, effort would might be better invested in creating a cell structure that isolates access to information in terms of the social graph.

Or to put it another way, an organization that relies on technical means to maintain secrets is still subject to infiltration. Wikileaks shows how readily organizations with dedicated and expert security staff and meaningful budgets are compromised by lack of or weak compartmentalization. A Snowden knockoff just walks out the door with a thumb drive of documents and hands it over to people who aren't supposed to have access bypassing NSA level security. And that's in an environment where people are rigorously vetted, not one looking for volunteers to the cause.

If I have an issue with the answer, it's that it conceives of an adversary who is 'just like us'. But plant a bug. Tape a cell phone to a car. Hire a honeypot. All will bypass an iPhone and disk-encryption and the local police can do any of them legally with a little effort and just about anyone with a will and a few hundred dollars can do them illegally with even less effort. And in the political realm there are lots of people with lots of will and more than a few hundred dollars at risk.