Boston is at a crossroads'one that is every bit as transformative as the epic battle between the Brahmin establishment and the emerging Irish political class in the 19th century. When, in 2013, Mayor Thomas M. Menino decided to step down after 20 bumptious years at the helm, 12 contenders vied for the office, endlessly debating how to balance the 'old' and the 'new' Boston. Veteran political analyst and WGBH public radio pundit Peter Kadzis observed that only one issue commanded the candidates' consensus: the housing crisis. 'On that, you didn't see the usual sniping and cheap shots. The issue is just too serious.'