South Korea and Japan both had the ability to shoot down the missile as well and neither one did it. I would assume if they saw it as a threat then they would have done so.
to wait is too late
there needs to be a precedent set : NK launches = regular opportunities to put to use our anti-missile defenses .
Which are probably ‘so secret’ we don;t want anyone to know , and thus no real deterrent at all .
USE um or lose it