There is a very close relationship between the two incidents as both were carried out by invading armies faced with armed civilian resistance to their occupation.
The difference is that a determined effort was made to bring the perpetrators of Oradour to justice while no attempt was made to bring the perpetrators of Porto de Mos.
Except in the court of history as convened on this Forum.
I think it is about time you brought forward Massena's orders on the correct treatment of civilians in Portugal in 1810-1811.
dg