As the news broke this Tuesday that Dublin’s Metrolink would be further delayed by an inevitable judicial review, I was reminded of the multiple rail trips I took across Paris over the few days I spent there last week.  As I zipped along some of the already world-class public transport infrastructure, large building sites marked “Grand Paris Express” popped up every few minutes across suburban areas. Some were right outside the front doors of apartment blocks. Others featured deep excavations at the junctions of major existing rail and road networks. The disruption was evident, but it is not for nothing:…