The Cold War
Me: Well, I know that a lot of people think that the cuban missile crisis was it but it was actually a lot longer. The whole thing lasted like 5 or 6 years. (my answer was much longer but for the purposes of this post, that is what I said)
*a few minutes later after I got curious and looked it up on wikipedia*
Me: okay, so apparently the cold war lasted like 50 years.
Roomate: hmm... who knew?!
Interesting stuff on Wikipedia about it.