Ignoring a retaliation site?

Solution 1:

Ignoring a retaliation strike (or as far as I can tell, most missions) will cause the Resistance in that region to "scatter". You will no longer have contacts in that region, and the monthly supply reward they give is permanently reduced if you do make contact with them again. If you have a continent bonus for that continent, you will lose it until you make contact with the region once again.