Boeing Co (BA  ) shares have looked to be in terminal decline in recent sessions after its 737 Max 9 Alaska Airlines jet blew out a door panel in mid-flight over a week ago. But the possibility of higher defense spending in 2024 could come to its rescue.

Boeing's list of military hardware is impressive and used throughout the world. It includes the Apache attack helicopter, the Chinook carrier and the B-52 bomber among its well-known brands, and various autonomous systems and missile strike hardware among its lesser-known capabilities.

These could all be on the shopping lists of Western nations in the coming months as tensions heat up in the Middle East and Red Sea areas. Not to mention, the near two-year-old conflict between Russia and Ukraine.

U.K. Minister Calls For Increased Defense Spending

In a speech at Lancaster House on Monday, U.K. Defence Secretary Grant Shapps declared the post-Cold War "peace dividend" over.

"Now is the time for all allied and democratic nations across the world to ensure their defense spending is growing," Shapps said as he described a world "moving from a post-war to a pre-war" environment.

In the U.S., the defense budget has increased every year since 2016 and the 2024 budget for defense was $886 billion. To put that in context, the budgets for education and health - in fact, everything else in the discretionary budget - came to a total $773 billion. More than half of this can be expected to be spent on contractors.

So which stocks are likely to benefit from this estimated $450 billion banquet?

U.S. Defense Stocks

One of Boeing's chief rivals is Lockheed Martin Corp (LMT  ), which supplies the famous Black Hawk helicopter and the F-16 and F-35 jet fighters, was already well positioned for increased defense spending, counting around 50 countries among its customers.

Lockheed also delivers autonomous aircraft - or drones - and is actively incorporating artificial intelligence systems to "revolutionize the human-machine relationship," the company said. Lockheed Martin shares are up 2.2% since the end of December.

Northrop Grumman Corp (NOC  ) makes the iconic B-2 Stealth Bomber, a range of air and underwater drones as well as electronic targeting and surveillance equipment. Its shares are up 2.8% in January.

General Dynamics Corp (GD  ) makes the Abrams Tank, and while the U.S. and its allies are not yet involved in any land wars, the company also supplies military information technology systems. Its shares are down 2.7% in January.

Outside of these well-known names, are some smaller groups such as TransDigm Group Inc (TDG  ), which makes parts for some of the above companies. Its shares are up nearly 4% so far in January.

Parsons Corp (PSN  ) is a similar-sized mid-cap that supplies advanced technologies to military and governmental organizations. Its shares are up 5% so far in January.

The best-funded exchange-traded fund, which holds most of the above and more, is the iShares U.S. Aerospace & Defense ETF (ITA  ). Its shares have fallen by around 5%, however, largely due to the high weighting of Boeing in its holdings.