The Axis & Allies style Vietnam Game did over $113k on its KS, so there is a frisson of interest somewhere in the conflict. We are also past the 50th anniversary of Tet and heading towards the other 'end of war' events, so I imagine that trickle of interest to grow a touch.
That said the Great War Centenary barely ignited interest in that in our little world, so I'm not betting on that.
You forgot to add Zombies And Sexy Alians to the mix.
Mere fads. Seriously wargaming gold is in what I said, with maybe American Civil War if you just want to get a little together for your retirement.