WASHINGTON — Iran fired a Shahab-3 medium-range missile on Wednesday, a United States military official said, playing it down by saying that it did not pose a threat to American or other Western shipping or military bases in the region.

The missile was launched from the southern coast of Iran and landed east of Tehran, the official said on Thursday, adding that it flew about 1,100 kilometers, or about 680 miles, and stayed inside Iran for the entire flight.

The official, who spoke on the condition of anonymity to discuss intelligence analyses, said that American officials had been closely monitoring the test site as Iran prepared the missile for launch.

Despite the Pentagon’s effort to minimize the strategic importance of the launch on Wednesday, it appears to be a political statement by Iran, acting both as a carefully calibrated effort at escalation — and as a message to Europe.