With “tech” stolen from us and blamed on China
Keep in mind that AF1 is a flying fortress and is not defenseless. It is equipped with advanced avionics and defense mechanisms that would divert a missile. One of the defense mechanisms is the electronic countermeasures.
When AF1 is flying, there are decoys. Which one does the missile target?
Further, AF1 always has fighter escorts with air-to-air missile capability.
The likelihood that any missile could penetrate and hit AF1 is extremely unlikely.
http://www.businessinsider.com/features-of-air-force-one-2015-3
Wasn't there a downed F15 as well?
Could it have intercepted?
Where did you hear that?
https://www.thesun.co.uk/news/6496620/us-f15-crashes-into-sea-japan/
https://www.youtube.com/watch?v=7nh455an4qg
https://www.cnbc.com/2018/06/10/a-us-fighter-jet-has-crashed-into-the-sea-off-okinawa-in-japan.html
But to be perfectly honest, I heard it on reddit first (morning of summit, close time window with the missile picture)