I want to know the answer to the following question:
What type of countries have set branches for territorial air defence?
All the background I'm provided with is that "This is in contrast to some (largely communist or ex-communist) countries where not only are there provisions for air defence in the army, navy and air force but there are specific branches that deal only with the air defence of territory, for example, the Soviet PVO Strany.". Is that enough to answer the question?