Quoting Jason White (jason@jasonjgw.net):
No, but in this case I think the metaphor (associating invocation of Article 50 with pressing the button that triggers a missile launch) is apt in the context of discussing the immediate and grave consequences that may follow - capital flight, stock market decline, etc.
Compare the reaction that occurred when the result of the vote was announced.
On my recent river cruise with my wife up part of the Danube River, we were wondering which of these fine cities might become the new European capital of banking and commerce, now that the City of London is being abandoned almost like it's the Plague Year, and the London bubble is a thing of the past. Vienna would be really, really good for many reasons. (I don't think it will happen.)