It is a mixture of extreme TDS, anti military, and anti US sentiments. Most lefties have such an irrational hate of Trump they would rather see the US fail than Trump get credit for a success. Many lefties have a low view of the US Military and also think everything in Europe is better than America.
<< It is a mixture of extreme TDS, anti military, and anti US sentiments. >>
Plus pro-jihadi sentiments — the red/green alliance.
And of course reflexively anti-Israel sentiments, which is the strongest motivating factor for many.