Defense contractors are winning on Wall Street, as the uncertainty of a war with Iran and increased tension in the Middle East continue to fuel substantial gains in the stock market.

While oil prices surged the highest Monday, jumping more than 6% over fears of a global supply shortage, companies that build military equipment weren’t far behind — Lockheed Martin and RTX, formerly known as Raytheon, gained 3.3% and 4.7% respectively.

Shares of Northrop Grumman jumped the highest, ending the day up about 6%.

As the DOW Jones Industrial Average fell 0.2% and the S&P 500 finished flat, all three of the world’s largest defense contractors hit new 52-week highs, according to Barron’s.

The major weapons companies are benefitting from the US strikes in Iran over the weekend, but have seen a consistent tailwind dating....