This may be the end of the bull market

It was completely understandable that airline passengers would have a sensational fear of flying immediately after the tragic events of Sept. 11th. Nobody wanted to become the next victim of a barbaric terrorist attack; and flying on airplanes seemed to be nothing but an anxiety-filled event complete with a mental list of prayers if anything horrific happened.

In the months that followed, as passengers regained their courage to fly, concerns turned to a different fear: A plane being hit in mid-air by a surface-to-air missile. News reports and media pundits decided to play expert by letting would-be travelers know the most vulnerable times to be on a plane are during approach and immediately after take-off. After all, a terrorist would have an opportunity to attack when the plane is closest to earth; and likely, remain camouflaged on the ground, thus making it difficult for police and the public to discover.

Tune in to CNBC's "Closing Bell" on Wednesday, July 23 from 3-5pm. Todd Schoenberger will be on to talk about whether this is the end of the bull market.

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After Thursday's stunning news about Malaysia Airlines MH17 being targeted, and hit, with a surface-to-air missile — while comfortably flying at a cruising altitude of 33,000 feet — renewed fears of travel are now top-of-mind. And even though the aftermath remains to be felt in political and financial circles, the one thing many Wall Street analysts are wondering today is if this will be the trigger moment to send markets reeling.

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Wall Street professionals, particularly traders and analysts, are routinely asked what will be the "moment" to signal an end to the current bull market. After all, despite a polar vortex, a 2.9-percent drop in first-quarter GDP, and excruciating geopolitical events in Syria, Iraq, Russia, Ukraine and Israel, this stock market has persevered and continues to reach higher highs.

There doesn't appear to be anything in sight to support the start of a bear market.

At least, until Thursday.

We have dozens and dozens of reasons why stocks are moving higher, regardless of the aforementioned events, which have traditionally signaled massive selling on Wall Street. One reason, however, that rarely receives any attention is this country's passive approach to violent conflicts.

Read More Global turmoil may punish complacency: El-Erian

With the exception of the raid that killed Osama bin Laden, the U.S. has really taken a backseat approach to becoming engaged in any sort of conflict over the last six years. And, if we do strike, it typically is at night and on a weekend. Therefore, by the time markets reopen for trading on Monday morning, our 140-character attention span has had a chance to digest the news and look past it rather than "knee-jerk" react and artificially push valuations lower.

But this time is certain to be different. There are no "red lines" or "sanctions" or even ultimatums. The souls taken on that plane were doing what the victims of Sept. 11 were doing that doomful Tuesday: They were living.

The victims of MH17 are just now becoming public, and on a global scale. As USA Today reported, there are the Maslins — Otis, 8, Evie, 10, and Mo, 12 — who were traveling with their granddad on their way home to Australia from a family vacation. Their parents stayed behind in Amsterdam to take a later flight.

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There was the sole American on board, Quinn Lucas Schansman, a business-school student living in Amsterdam who had dual citizenship in the U.S. and the Netherlands.

There was the up-and-coming chemist, Karlijn Keijzer, a graduate student from the Netherlands studying at Indiana University, who was working on developing an anti-cancer drug that could also stop the progression of Alzheimer's disease.

And there was the Malaysian actress, Shuba Jaya, who was returning to Malaysia with her husband and their 2-year-old daughter, after a visit to her in-laws in the Netherlands.

In other words: We can see the faces and they aren't wearing uniforms or carrying guns. They're simply just like us, and this is why the White House will be pressured into doing something more than placing some pointless economic sanctions on Moscow. If you ever needed a breaking point to get this country to show its muscle, this is as significant as it gets.

If you want to test your knowledge on the immediate reaction of violent conflicts on the stock market, just turn your attention to the trading charts of airlines in the seconds following the MH17 attack.

When news hit the tape at 11:06 ET, airline stocks plummeted regardless of the rest of the market holding steady to figure out what was taking place. For instance, Delta Airlines dropped 3.3 percent up until 11:32 ET, the minute the first reports informed the world the attack was specific to one flight, and not others around the world.

Shares of JetBlue and Southwest reacted the same way, with declines of 2.4 and 2.1 percent, respectively, during the same 26-minute period. Even the Dow Jones travel and leisure index — consisting of hotel, restaurant, airlines and casino stocks — had given up two-thirds of one percent during that brief period. Once news broke in the afternoon that it was a surface-to-air missile, the broader averages gave out and all stocks followed, pushing averages to daily lows by the close.

Now that the public has a fresh fear of flying, the short-term prognosis for travel and leisure stocks is dismal. If you had to pick one sector to stay far away from for the rest of the year, this would be it. No question, recreational travelers will not feel comfortable knowing the entire flight will be a complete vulnerable experience. Look for damage to be done to cruise stocks, as well, because of these concerns.

The question will be the United States' eventual involvement and impact on the broader averages. As many have said, the one factor to become a catalyst for a prolonged period of selling will be a global geopolitical event; and the downing of flight MH17 may very well be the trigger to pull the bears out of hibernation.

Commentary by Todd M. Schoenberger, the founder and managing partner of LandColt Capital LP. He also serves as Portfolio Manager of the LandColt Onshore and Offshore Funds. Follow him on Twitter @TMSchoenberger.

Disclosure: Neither Schoenberger nor the LandColt Fund hold any positions mentioned in this article.