It's already priced in the stock. No stock just goes up without some dips. You have to take some gains when stock spikes up, never buy going up buy going down! You will make more money and increase your shares!
For starters, he has not signed the Bill yet ... and, the shorts are working it ... and, retail guys who are asking themselves "why is it dropping if it is good news" are selling ... before he signs ... before it hits the news ... before an article is written ... before Cramer talks about it