It's the same as it ever was. You should read about the decades-long drift to war (as opposed to the actual war itself) that was the 2nd Pelopennesian War. Cross-out the personal names and geographic locations and its indistinguishable from the modern world. Post WW2 debates are the same as post OIF debates.
OK, so we can transmit more data today than they could with a trireme or a crystal radio set but humans always fill all vacuums and opportunities to the fullest of their capabilities. It's also pretty amazing how much people WEREN'T propagandized in those days despite the absence of industrialized media and the innewebz. Sure they had their liars and manipulators but just as today they had their competitors and alternates.
Stop dreading the future when everything you fear has been confronted thousands of times throughout history. Study what worked and what didn't work and then work towards what has been proven.
We are not new, unique or special. Our lives and the struggles we are observing are very, very, VERY mundane. We are not God's chosen. We have no historical mandate. What we see is so absolutely ordinary it should be almost tedious.