Martijn I can actually come up with several legit reasons for a government to run their own CA. Governments are moving communications about important and personal things like healthcare online, and having these services encrypted with government signed certificates are a very good way of handling things. The real problem is that underlying CA structure where any root CA can MITM any website. Running add-ons like CertWatch, Certificate Patrol, and the Perspective Project can mitigate this, but not for average users.