I seriously believed for some time that Watergate was about a huge (and apparently long-lasting!) flood caused by the president who had screwed up and left a big Gate open and lots of Water came through it, which explained why people were mad at him. I was convinced that this had all been on the news. My guess now is that I had been seeing TV reports about major flooding on the East Coast in 1972 from Hurricane Agnes, at about the same time as the Watergate burglary, so when they started talking about Watergate, I just combined the news stories in my mind...
A childhood belief about politics

others believed things like this
- I was pretty small when Nixon was President. I thought "Watergate" was a type of alligator.— Ginger
- I believed Walter Cronkite knew everything, that's why they let him do the news.— Dixon
- I always believed that we lived in Manchester (we didn't) but it was always the main place on the local news!— Richard M
- I thought if I left the door open too long, a dog would come from the cupboard in the washroom and eat me
Anon - I used to think for a very long time, that spam was left over animal parts with salt.— Ebony
- I used to believe that if you left crumbs out for a long period of time, they would turn into ants.— Bylaberrie