[qaq]

That does not sound even remotely plausible there are way more mundane activities that all require IDs.The study like that is purely meaningless because you can not control for all the other variables of societal change in the same time frame. I can take any other variable and claim it's the cause of the decline. Also I spent most of my life in Europe in way more left leaning countries than US and this is not even remotely on the radar of anyone.