It wasn't America's finest hour. The clash between protestors and police in Ferguson, Missouri, this summer in the aftermath of the fatal shooting of the unarmed Michael Brown caused racial tension and other thorny issues to surface in a country that prides itself on fairness and opportunity.

One thing that has gone largely unreported since the unfortunate situation is that shares of TASER International (AXON 2.64%) have soared more than 35 percent since the Aug. 9 shooting. Shares of the leading stun gun maker didn't shoot higher right away. It actually closed unchanged on the first trading day following the incident. However, as protests began to heat up in Ferguson and the media focused on the less-than-lethal alternatives for confronting a potential suspect, TASER began to gain in popularity. How would this incident have played out if the cop had subdued Brown with a TASER instead of firing off several rounds? 

TASER is also a leading maker of body-mounted cameras that many in law enforcement are starting to wear -- including, just this week, officers in Ferguson.  If that had been the case before the incident, we would have a clearer snapshot of what actually happened in the face of conflicting reports as to whether Brown had charged at the officer or not.

It's an unfortunate incident all around, but investors also realize that TASER stands to sell a lot more of its namesake weaponry and wearable cameras in the future. It's grim but true: TASER is at its best when the country is at its worst. It's not alone. Let's look at a few other stocks that have historically benefited from times of turmoil.

Eye of the storm
Natural disasters can be pretty fierce. Hurricanes, earthquakes, and tornadoes can be devastating. We know who the losers are when disasters strike: Residents are forced to clean up and rebuild. The big losers on Wall Street are the property casualty insurers that will be on the hook for the covered losses.

However, there are two sides to every tragedy. Home improvement superstores are slammed with customers in the aftermath of major storms. Home Depot (HD 0.86%) and Lowe's (LOW 1.49%) are there to provide replacement products and repair tools. A lot of the money being handed to homeowners in insurance claims goes right back to Home Depot and Lowe's. 

It doesn't even have to wait for insurance claims or the aftermath of natural disasters. As hurricanes near landfall, residents flock to the hardware giants to load up on window-fortifying plywood, generators, and emergency supplies. 

War on terror
Military conflicts will probably never go away, and clearly that's horrific in terms of the lives of soldiers and civilians who die in confrontations. However, there is no shortage of publicly traded military contractors that thrive when countries need updated or replacement machinery.

Let's move beyond the major military contractors to talk about iRobot (IRBT 2.23%) and AeroVironment (AVAV 5.73%). The first name is probably a household name because it's the company behind the Roomba vacuum-cleaning orbs. Automated dirt suckers around the home have made iRobot a consumer-facing darling, but it also puts its robotics technology to good use on the battlefield with its PackBot robots that can perform surveillance missions while also disposing of any roadside bombs and explosives. AeroVironment is a leader in unmanned aircraft vehicles. These drones fly on reconnaissance missions to see what the enemy is up to. The drones are also indispensable away from the warfront, as they can also monitor storms and other pending weather disasters.

AeroVironment and iRobot thrive when terrorists strike or wars escalate, but investors are also buying into two companies that assist in achieving military goals and objectives without putting human soldiers in harm's way.

There is never a shortage of bad news out there. It will never go away. Investors don't have stay on the sidelines, even as they respect and mourn the calamity.