It worries me that it has been a long, long time since there has been any significant correction in the stock market.
In all my years, I have never seen a market go up for so long without any significant corrections. Is it the passive investment trend? I don't know and I don't think anyone really knows. Maybe people will say it is different now.
My experience tells me it is never this totally different. I say it is "the same, but different". The major attributes of the market have always been the same, although minor currents are different. Are we in for a comeuppance?
I definitely think it is a time to be cautious. My purchases are very infrequent now. There is so little that is really interesting to buy. Any of my "high flyers" are owned at prices that are a fraction of the current prices. I have pruned those securities that will bode relatively poorly in a down market (though you never really know).
The yield curve is flattening and the new tax regulation is "putting gasoline on the fire".
Keep safe and watch you don't get sweep away with the herd!