I notice that Mark Gilbert of Bloomberg, linked by Barry Ritholz, also invokes the wall of worry.
Google trends shows more interest in it last decade, not so much any more.
Maybe when it starts to become a thing again, that will be a clue that it is about to collapse, and the top is in sight. Which is not the case now.
As the market bump along near all-time highs, people are spooked. Trump spooks them. Clinton spooks them. Brexit spooks them. China spooks them. The Fed spooks them. Rich P/E’s spook them. There’s plenty of spooks out there. It is the classic wall of worry.
However, as the link notes,
a continued advance is much less certain if the wall of worry forms near a major market peak, in which case a subsequent decline is more likely
So we will see. I will go with the conventional wisdom for now, and say the markets will climb this wall of worry, and that this is a good time to be looking for stocks.
Note too that by definition, after a major market peak, stocks fall and the wall of worry breaks down. But how long did it run before that point? Maybe we’re 10-20% away from that major market peak.