In a historic first, the United States military announced the opening of a permanent U.S. base inside Israel on Monday.

The American base will be manned by U.S. Air Force personnel, and will be focused on air defense. The base is located within an existing Israeli military base in the Negev desert in southern Israel.

But as Israeli military officials were quick to point out, while a permanent American military base in Israel is indicative of extremely close American and Israeli military relations, the base has been in the works for over two years. Israeli Air Force Brig. Gen. Tzvika Haimovitch said that the “connection between the armies, the commanders, the [air] forces, is stronger than this or that administration.”

Despite the somewhat cold relations between the Obama administration and Israel, military aid and cooperation between the two countries only increased during the Obama years, and will certainly continue to grow under President Donald Trump.

The air defense system the U.S. Air Force brings to the table will augment an already robust system of counter-battery missiles employed by the Israelis, who live under continuous threat of short and medium range missiles fired from the Gaza Strip and Hezbollah militants in Lebanon.

While the small size of the base and relatively few American service members means an overall negligible effect on the U.S.-Israeli operational relationship—compare a few dozen Air Force members to the tens of thousands of Americans based in Germany—the base is nonetheless a symbolic recognition of the growing threat faced by Israel from Iran and its expanding missile program. The U.S. has had soldiers deployed to Israel for years on a rotational basis. They have been operating the X-Band radar system as part of a joint air defense mission.

Israel has long said Iran remains an existential threat, citing their aggressive actions in southern Lebanon in supply and arming Hezbollah militants with numerous and increasingly advanced missiles. Israel and Iranian proxy Hezbollah are both preparing for what appears to be another inevitable war.

Image courtesy of the Israel Defense Forces. Image shows a joint U.S.-Israel air exercise.