Walking through the bustling conference space at 133 Houndsditch in central London, Simon Coveney is stopped for photographs and handshakes. He’s complimented for his work on the Brexit negotiations, which helped ensure that no hard border would return to the island of Ireland. The former tánaiste was one of three key negotiators alongside former taoiseach Leo Varadkar and the recently departed finance minister Paschal Donohoe, who helped build a European consensus of support around Ireland’s unique exposure to Britain’s decision to leave the bloc. To Coveney, there was an irony in the fact that all three men had been “shaped…