What if Éamon De Valera had agreed to support the Anglo-Irish Treaty in 1922?
Well, no Civil War. Probably

OTOH, the situation in the Six Counties could get even nastier. Both Collins and De Valera would be in favour of supporting the Northern IRA. Not so much to end Partition but to defend Northern Catholics against the Loyalist mobs.

Had they been too effective Churchill would have tried to reoccupy the Free State .

On The Gripping Hand, a unified IRA and a less weak Free State might have been able to insist the Boundary Commission did a better job. A less tortuous border would be a help today.
 
Yeah the Civil War is avoided and Dev probably doesn’t become the hate figure he is for Unionists IOTL.

Anti-Treaty republicanism will still exist but will be smaller as it won’t have a figurehead. It probably becomes a more Northern based movement far earlier than it didnt IOTL.
 
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