I do get the conservation of airspace thing, but blowing up a transport you're escorting out of your territory is an act of war. Whilst there might be half the Rheinland Dev Chat looking to re-enact winter 1941, it can be done a bit more subtly than that.
Mind you, the character was adversarial. It just seems like there'd be a major diplomatic incident because of that. Or you could pay the Unioners to do it.
THE SYNDIC LEAGUES
(A co-operative of Rheinland's Shipping Unions, retired from a life of piracy.)