How would today’s technology prevent a “union blockage” from being successful?

Union blockage with today’s technology:

Union blockage came into existence in America intending to block trading during the civil war. The goal was to prevent necessary supplies from reaching the confederates since the army felt that if the war lasted for a long time, the best supplied military would win the battle.  

In the recent years, technology has changed international trade massively and has also reduced other trade wars and addressed international tariffs. Union blockage could be prevented by the use of methods that help identify shipping containers easily.

Europe needs to build a trump-like wall that will spread across europe making it impossible for migrants to cross they need to spread pig guts all over this wall so the muslims will never consider crossing into europe..you might be asking "can't they just fly over with planes? " well yes they can so we will install thaad missile protections system to shoot down any aircraft that violates europe's air fourth would be to start a fourth reich in germany.. last but not least.. make europe great again!

The answer is d) rift