Hell no.

Whatever pundits, media, politicians and military establishments say today or soon fighting small wars - which often involves COIN - are a historical constant.

You could almost do a Ph.D. on COIN disappearing from view and returning. Historical continuities and new aspects from 'x' to 'y'.

Did COIN change after 9/11?

Keep well away from contemporary debates.

Identify a clear date line, e.g. end of French rule in Algeria; align with your area of research and access (to published and verbal accounts).