The Trump Administration gave the go ahead to sell $2.2 billion dollars worth of missile defense to Japan. Previously delayed due to the government shut down, the missile defense sale took was approved January 29th, 2019. The sale included two Aegis Ashore missile interceptors.
Significance: This sale signifies US endorsement of Japan’s missile defense systems buildup, due to multiple prior sales of similar systems to Japan that included many Aegis defense systems and destroyers . Because the US is expected to review the missile defense systems in 2020, it is important to note that the scope of missile technology and targets may increase as a result.
See article here: https://www.armscontrol.org/act/2019-03/news-briefs/us-approves-missile-defense-sale-japan