On a warm summer day in 1946 I find myself, somewhat improbably, at the helm of a U.S. Navy ocean tug, threading through a crowded, palm-fringed Pacific atoll called Bikini. We stay only long enough to anchor the derelict ship we’ve towed here from the Philippines. Several days later, making slow progress east to Honolulu, we learn that the wreck we had pulled into that pristine island sanctuary had been obliterated — along with everything else in the lagoon — by two atomic bombs. More than a few of my shipmates are bitter that, unlike others, they had been denied an extremely close look at the destruction. But for most of us it is simply an isolated event, one among many in those rather bewildering post-war days following the bombings at Hiroshima and Nagasaki.