Last week, I was chatting to The Currency’s Ian Kehoe about who would be an interesting person to talk to about Sinn Féin. Since the by-election results the previous weekend, the coverage had been relentlessly negative. The progressive alliance was said to be splintering, with other parties questioning if Sinn Féin could truly be described as a left-wing party, given their abstention on an abortion bill and their mixed messages on immigration.  We talked about the various insightful commentators on the issue and who could provide some analysis. Then I suggested I might text Eoin Ó Broin and see if…