Opponents say the government's policy is 'a disaster waiting to happen'. [=something that will probably have a very bad or tragic result]
The government's policy is 'a recipe for disaster'. = The government is 'flirting with disaster' by pursuing this policy.
The earthquake was one of the worst 'natural disasters' [=a disaster caused by natural forces] of this century.
(..) Look, nobody underestimates the importance of the job you chaps are doing. But what happened in Budapest last year, that was a disaster. With respect, sir, it wasn't one of your civil servants that got killed, was it? Now this isn't about soldiers in trenches any more. (..)2011 Tinker Tailor Soldier Spy