The military industrial response to Vietnam protests and the utter unpopularity of an evil war that continues for decades and still has scars on America let alone SE Asia for me is the defining turn post WWII. Ike himself, as a general, directly stated the greatest threat to American democracy was the military industrial complex. The threats have multiplied since then.

The Atomic Cafe is a great documentary made solely with archival footage including the Ike quote above. It's chilling hearing that said 60+ years ago by a general and sitting president.

You're not wrong, but there was plenty before Reagan and more to come.

JFK's assassination.

Edit: Fun little song

I blame Polk, personally. But Reagan gets some credit.