Reporting from Seoul — 

In the last five years, North Korea has test fired more than 50 ballistic missiles in an effort to perfect a technology that its opponents fear might someday deliver a nuclear weapon.

So the launch of a missile on Sunday that soared 300 miles across North Korea from west to east before crashing harmlessly into the Sea of Japan might have been another of those tests.

Or it could have been a test of President Trump.

The reclusive country’s leader, Kim Jong Un, didn’t detail his government’s motives for launching the missile — the first such test since before last year’s U.S. presidential election. State media on Monday morning characterized it as successful. North Korea watchers suggested several possible reasons for the timing, both practical and geopolitical.