For anyone doubting this, I direct you to this:
https://en.wikipedia.org/wiki/List_of_recessions_in_the_United_StatesBased on history, even post-WW2, we are due for one any day now.
As Beet said, cycles have gotten longer recently but it still seems extremely likely we get one before 2020's elections. I'd even say that it's very possible before 2018's midterm, even if just slightly. I think the better question is how bad will it be? Have persistently low interest rates given us too little to fight back with?
I think it goes without saying that I hope we don't get a recession, but my hopes don't trump reality. That being said, Republicans ought to take stock of this before gloating too much. You guys are going to be blamed for this one too
(as is standard for whichever party controls the White House), and thus continuing a trend of Republicans presiding over every recession we've had since the late 1960s.