Can't blame unions, considering how easily Europe gets it done. Most likely issue is that in the US, every landowner and minor municipality is empowered to delay and obstruct these projects and thus milk them.
Polish environmental law is quite notorious for being deliberately easy on developers (at least outside national parks), which translates into a lot of construction activity.
OTOH Californian CEQA is such a NIMBY/BANANA weapon of mass anti-construction that I have heard of it, despite being located a third of a world away.
Both sound like intent.