S & P 500

So, im seeing this index sitting right at all time highs.  It is at 2120 this very moment.  Brexit was a major event in the news but very minor to the US in reality.  It still cared a lot of people into making trades.  Now we know people are listening to economic news.  Maybe that was the wake up call.  Maybe the big fall is being set up.  You cant have a market decline if the market participants arent reading economic news.  If bad economic news will now catch the eye of many people, then a major event that is actually major to the US in reality can cause a market selloff.  It is interesting trying to figure out what would cause a decline but in the end, predicting is impossible unless u actually have super powers.  What i do know is that we are vulnerable to a selloff.  I have no clue what will or could cause it.  When a selloff happens, it is because enough people decided to sell at the same time and more join in as it gets worse. Then vultures like me start circling.