Anybody who has traded for enough time knows not to take short term sentiment of the financial markets too seriously - the markets move on drama. They plunge on unrest/reality not matching expectation (yesterday), recover very quickly on realisation that things are not as bad as they seem and they soar on any type of hope (today), however ridiculous it may seem. It is a snowball effect.
It doesn't mean anything. Today is just the first day people have realised that Trump is one man and the idea that he could ruin a nation by himself is a ridiculous overreaction.