"It would be the first American strategic missile defence site outside U.S. territory, and would be designed to defend all of Europe against intercontinental-range missiles - primarily those launched from the Middle East."
I think you are missing the strategy here.
You need to read between the lines. If it were to defend Western Europe, then it would be a NATO base, or other European military installation, but given that is is going to be a United States site, you need to look at why it would need to be there.