Due to Russia’s invasion of Ukraine earlier this year, defense stocks naturally gained significant relevance. Moreover, the aggressor’s escalation of the military conflict — met with stout Ukrainian resistance and successful counteroffensives — implies that the crisis will continue on for some time. Cynically, this dynamic boosts military-related investments, but that’s arguably not the main catalyst. The core reason for defending Ukraine against Russian aggression comes down to prevention of future catastrophes.

Indeed, the U.S. and its allies share various rivals. Aside from Russia, North Korea recently escalated tensions in the Asia-Pacific region with ballistic missile tests. China may also feel emboldened to forward its international interests in the future. To try to mitigate and avoid potential future conflicts with these and other nations, the West is largely responding to Russian aggression with its support of Ukraine and investing its own defense systems.

Ultimately, defense stocks protect global democracies and the sovereign right of self-determination. Over the long run, that’s a net positive for all of us.

Raytheon Technologies (RTX)

One of the more prominent defense stocks that happens to deliver a solid discount, Raytheon Technologies (NYSE:RTX) partnered with Lockheed Martin (NYSE:LMT) to produce the Javelin anti-tank missile. Used to great effect by Ukrainian resistance forces, the Javelin prevented Russian heavy armor from infiltrating Kyiv. Later, Raytheon’s Stinger anti-aircraft missile provided critical cover for Ukrainian ground troops.

Despite the enormous relevancies to the current conflict, RTX slipped more than 4% on a year-to-date (YTD) basis through Oct. 3. To be fair, the major equity indices suffered double-digit losses over the same period. As well, the red ink provides an opportunity for contrarian investors to scoop up a discount. Over time, as Russia doubles down stubbornly in its war, the need for reliable defense stocks increases significantly.

Presently, Gurufocus.com labels RTX as fairly valued. I can’t complain with this framework, even though it features a forward price-earnings (P/E) ratio of 14.4 times, under the industry median of 16 times. Most importantly, future demand for Raytheon’s products should increase, fundamentally making it an undervalued opportunity.

Huntington Ingalls (HII)

Among the most relevant defense stocks to buy, Huntington Ingalls (NYSE:HII) represents the largest military shipbuilding company in the U.S. Moving forward, two catalysts should help propel HII in a northly direction.

First, the Coast Guard struggles to find recruits to fill available roles. As defenders of America’s maritime borders, the Coast Guard needs to be ready at all times to protect against threats. With dangers at sea rising in recent years, the federal government may call upon Huntington to address critical needs.

Per Gurufocus.com, Huntington Ingalls is fairly valued. It’s possible that HII is slightly on the undervalued scale, given its forward PE of 12.6 times. As well, the underlying company features solid revenue growth and robust profitability metrics.

L3Harris Technologies (LHX)

A defense contractor and information technology services provider, L3Harris Technologies (NYSE:LHX) represents one of the top defense stocks tethered to the digital front lines. As well, the company provides advanced solutions across the spectrum of military needs, affording L3Harris incredible flexibility.

Currently, LHX performs decently, though not outstandingly. Since the start of the year, LHX has gained nearly 5%. Looking ahead, investors will want to pay close attention to the company.

As with the other defense stocks, Gurufocus.com labels LHX as fairly valued. However, based on the urgency of the underlying sector, L3Harris arguably provides a significant discount. Even on paper, LHX features a forward PE ratio of under 15 times, ranked better than 67% of defense firms.

In addition, L3Harris enjoys excellent growth and profitability metrics. Its three-year revenue growth rate stands at 19.8%, rated better than 87% of its competitors. Also, its net margin is 11.4%, better than 79% of its peers.

Safran (SAFRY)

A French multinational company, Safran (OTCMKTS:SAFRY) primarily designs, develops and manufactures aircraft and rocket engines. In addition, Safran provides defense-related equipment and components. Perhaps most notably given the Ukraine conflict, the defense firm features a drones and robotics arm.

To arguably most American investors, SAFRY represents a little-known enterprise. Perhaps not surprisingly then, Safran shares have slipped more than 20% YTD. Surely, being traded in the over-the-counter market doesn’t help. At the same time, SAFRY may be one of the defense stocks that are too cheap to ignore.

According to Gurufocus.com, Safran’s business rates as modestly undervalued. On this front, the company features a price-to-free-cash-flow ratio of just under 16 times. In comparison, the industry median is 21 times. In addition, Safran enjoys decent profitability metrics, including an operating margin of 11.5%, ranked better than 75% of its peers.

Finally, SAFRY features robust momentum. Over the trailing five days — despite broader market volatility — shares gained 4%.

TransDigm (TDG)

Focused on the aerospace manufacturing industry, TransDigm (NYSE:TDG) represents a leading global producer of engineered aerospace components. Interestingly, under its Armtec Defense Technologies business, TransDigm provides infrared decoy flares to protect pilots against heat-seeking missiles. In addition, it also manufactures chaff to help fool radar-guided missiles. Should conflict zones heat up, demand for TransDigm products will likely increase.

Still, not everyone on Wall Street recognizes the forward-looking potential of TDG and similar defense stocks. Since the January opener, TransDigm shares find themselves down more than 12%. Cynically, though, this framework could change in a hurry.

From a purely investment perspective, market participants can’t afford to ignore how cheap TDG is. Per Gurufocus.com, TransDigm features a modestly undervalued business. Significant highlights include the company’s three-year revenue growth rate of 6.2% (rated better than 65% of aerospace firms) and net margin of 15.6% (rated better than 83% of its rivals).

Elbit Systems (ESLT)

Based in Israel, Elbit Systems (NASDAQ:ESLT) offers relevancies across a wide range of defense, security and commercial programs. This includes unmanned aircraft systems and electronic warfare and countermeasure systems. Given how the conflict in Ukraine articulated the need for intelligence and communications in modern warfare, Elbit should have no trouble marketing its platforms.

Compared to other defense stocks, Wall Street apparently recognizes the value undergirding ESLT. Since the beginning of this year, ESLT has gained 13%. However, over the trailing month, Elbit shares bled off about 5% of market value. Thus, from a technical point of view, prospective investors can grab a near-term discount.

Fundamentally as well, ESLT arguably represents a cheap name among defense stocks. Gurufocus.com rates Elbit as modestly undervalued. The investment resource provides an excellent breakdown of the underlying financial proposition. To put it succinctly, Elbit features strengths across the board with excellent growth and profitability metrics. It also features a decently stable balance sheet.

Ammo Inc (POWW)

The most speculative name on this list of cheap defense stocks, Ammo Inc (NASDAQ:POWW) designs and produces ammunition products for both recreational and law enforcement and military use.

The company stands among the more intriguing defense stocks. Last year, Ammo generated some headlines when it won a contract with the U.S. Department of Defense. Specifically, the government tasked Ammo to “design and manufacture multiple Ballistically Matched Multi-Purpose Rounds (BM-MPR) in support of U.S. military operations.”

To be fair, Gurufocus.com labels POWW as a possible value trap. Therefore, if you can’t stand volatility, you may be better served with undervalued blue-chip defense stocks. However, for the adventurous, Ammo features a three-year book growth rate of 68.6%, beating out over 95% of defense companies. Also, it enjoys solid profitability metrics to boot.

On the date of publication, Josh Enomoto did not have (either directly or indirectly) any positions in the securities mentioned in this article. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.com Publishing Guidelines.