Not sure that they will - after all, it is hard for them and le Resistance to plausibly chirp away about Corbyn being a threat to national security when they have been getting us involved in wars that result in an ever-increasing terror problem at home, when they have been getting rid of tens of thousands of military personnel, when they have been radically downsizing the emergency services, when they have been selling huge swathes of critical national infrastructure to foreign companies and governments, and when they have been pushing the amount of debt we collectively and individually hold ever upwards.
They would be on better grounds criticizing him for having a beard; at least none of them have one.