After years of harassment, an old United States enemy is mysteriously backing down

American military officials don’t have an explanation for why Iranian “fast boats” have backed down in the Persian Gulf, but they welcome the change, according to a report in the Wall Street Journal.

For years, the small watercraft — operated by the Iranian Revolutionary Guard Corps, and normally armed with a .50 caliber machine gun and/or rocket launchers — have harassed American warships and commercial vessels operating in international waters. Navy ships have, in the past, fired warning shots.

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Some have pointed spotlights at American ships and airplanes, presenting risk to pilots and operators. The Pentagon says “at least” 50 incidents have taken place in the past two years. They came to an abrupt end in August 2017, according to WSJ.

The cessation appears to be follow an order given last summer by the Iranian Supreme National Security Council. They reportedly ordered the Iranian Revolutionary Guard Corps to stay away from US Navy ships but to stand their ground in the channel.

Externally, at least, the Navy remains wary and isn’t willing to attribute the sudden evaporation of “fast boats” to anything in particular. US Navy Cmdr. Bill Urban of the Navy’s Fifth Fleet told WSJ that they were “not going to speculate on the reason for this recent positive trend in interactions, though we hope it will continue in the future.”

“They understand the administration’s policy at this stage is to put the spotlight on Iranians and portray them as the source of all evil in the region,” he added, calling Iran “certainly part of the problem” but adding that the nation would “like to be portrayed as part of the solution, not just the problem.”

While the small watercraft seem to have fallen back, Iran has ramped up the presence — and use — of drones in the Persian Gulf.

In two incidents in August 2017, unarmed Iranian drones approached United States aircraft and the USS Nimitz (CVN-68) aircraft carrier, according to the US Naval Institute.

In one incident, an Iranian drone came within 200 feet of an FA-18E Super Hornet.