There's some very long articles from the NYT and I believe The Atlantic or one of those long form mags on the topic. A mix of reliance on private contractors,

There's some very long articles from the NYT and I believe The Atlantic or one of those long form mags on the topic. A mix of reliance on private contractors, union demands and decentralized nature of all the bits and pieces of engineering, all of which needs to be coordinated and lined up. Places like France and UK and Japan are more centralized (and unionization doesn't lead to the strange MTA and other rules we see here).