Britain's departure from the 28-member European Union may be the start of something bigger, and far more chaotic.
Brexit has roiled world markets and divided other E.U. members, amid rumblings of other countries wishing to hold a vote on continued membership. One former diplomat told CNBC that the process of Great Britain leaving the community of European nations, which may take years, is likely to be fraught with peril and tension.
"It will be a messy divorce between the United Kingdom and the E.U.," says Richard Haass, president of the Council on Foreign Relations. So could Brexit be the beginning of the end of the European Union itself?
"Quite possibly, if not the end of it, certainly the change of it," the former State Department official told "On The Money" in a recent interview.
"The scary thing, the frightening thing about this vote is it may have set in motion trends (in) which the entire E.U. itself," Haass predicts, "will begin to unravel."
Haass, a Republican and former State Department director of policy planning, was a principal advisor to Secretary of State Colin Powell. He says other "exit" votes could be ahead, as populist movements in countries like France, Italy and Spain gain momentum.
"Other countries in the E.U. may want to have their own referenda, and the E.U. is wildly unpopular," Haass said. "I think it creates all sorts of questions about this thing called the 'European project'."