Ultimately, MicroStrategy (MSTR) - Get Report was a concept stock. Oh yeah, I know my verbs and how to conjugate "to be," so that's not a grammar/tense error.

I am stressing Mister

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because concept stocks have been so loved by this market that when the one that has mesmerized people

takes a fall, the lesser concepts, whether they are in biotech or telco or artificial intelligence or the Net, really get whacked.

What's a concept stock? Something that has a huge market-cap-to-revenue ratio. Those are the stocks that are going to continue to get crushed today, even as Mister tries to head in for a landing, thereby preserving 90 points, give or take a few.

That's where the worries will remain, even though we are now becoming convinced that MicroStrategy is the outlier.

Last week, we had a shock to the

Nasdaq

that was based on the notion that these stocks, even if everything worked out, were richly valued. Now with Mister, we find out that things aren't going to work out.

That's jarring, to say the least.

James J. Cramer is manager of a hedge fund and co-founder of TheStreet.com. At time of publication, his fund had no positions in any stocks mentioned. His fund often buys and sells securities that are the subject of his columns, both before and after the columns are published, and the positions that his fund takes may change at any time. Under no circumstances does the information in this column represent a recommendation to buy or sell stocks. Cramer's writings provide insights into the dynamics of money management and are not a solicitation for transactions. While he cannot provide investment advice or recommendations, he invites you to comment on his column at

jjcletters@thestreet.com.