Yep. That's what explosives do. Kennedy armed the package, but that is not the same thing as fuzing it. The fuze malfunctioned. Handling and using high explosives is rightly considered dangerous. There was a saying about the differing approaches taken by the U.S. and the U.K. to developing weapons. "The Americans would take something that would work, then make it safe. The British would take something that was safe, then make it work." A mishap involving an experimental weapon in operation is not "questionable." It is a tragedy and a mystery, but there is no more to say about it.