The other feature of the premature demise of trolleybus systems that replaced tramways was that this took place in drastic fashion (often in the 1960s) in countries where there were major manufacturers of diesel bus engines/chassis - UK, France, Germany and Sweden. Political conspiracy much? GM in USA wasn't the only culprit. As I said, none of those manufacturers even today have much to do with electric buses. There's big money in Diesel engines, not so much money in selling just a chassis that goes off to other manufactured to do the rest of the job.

Tony P