Tiocfaidh ár Lá is not a 'provo' slogan.
Its an Irish Language slogan, meaning our day will come,, in this context, the day of a socialist republic, and was popularised by the Irish Republican, and socialist prisoner of war Bobby Sands.
Republicanism in Ireland is the most progressive force, and has the most dedicated activists who are willng to stand up and be counted as they have shown in every generation.
socialist republican's are the most advanced cadres in Ireland.
I would have no problem with the Starry Plough as the group logo.