European rearmament, an evolving NATO posture and continuing conflict in multiple theatres have transformed the defence sector from a niche government supplier into a structural growth story. Here is what UK investors should know about BAE Systems, Rheinmetall, Lockheed Martin and Northrop Grumman.

What's happening

For most of the post-Cold War era, defence companies were a quiet corner of the Equity market. Order books were steady, dividends were dependable, but explosive growth was rare. War in Ukraine, escalating tensions in the Middle East, increased Chinese assertiveness in the Indo-Pacific and a general acceptance across Western governments that defence budgets needed to rise have changed the picture. Spending commitments from NATO members, surging artillery and air defence orders, and a renewed political appetite for industrial sovereignty have transformed the sector into one of the most-watched parts of the global market.

The result has been a striking rerating. BAE Systems in the UK has powered to multi-year highs. Rheinmetall in Germany has been one of the standout European stocks of recent years, briefly trading at multiples more associated with a high-growth software company than a tank-and-shell maker. Lockheed Martin and Northrop Grumman in the US, while more measured in performance, have continued to Fill order books with multi-year programmes in fighter jets, submarines, missiles and space.

For UK retail investors, the appeal is obvious: long-cycle Revenue, government-backed contracts, and a strong Dividend tradition in many of the major names. The challenge is that some of the easy upside may already be in the share prices. With several names well above their 52-week lows and only modestly off their highs, the question is whether the structural shift in defence spending is fully priced in, or just the start of a multi-year tailwind.

What's driving Demand

The first force is European rearmament. Following Russia's invasion of Ukraine, governments across the continent have pledged sustained increases in defence spending, often anchored to or above NATO's two per cent of GDP target. Some have gone further, signalling multi-year commitments to replace ageing equipment, refill munitions stockpiles, and acquire new air defence and counter-drone capabilities. This is creating a wave of orders that will take many years to work through Manufacturing capacity.

The second is the United States' own priorities. The US still spends more on defence than any other country, and recent budget proposals have continued to expand the topline despite political tensions. Programmes around sixth-generation aircraft, hypersonic weapons, naval shipbuilding, missile defence and space have all become priorities, supporting long-running revenue streams for the major American primes.

The third is the Indo-Pacific. Allies including Japan, Korea, Australia and the Philippines are stepping up their own defence investments, often coordinated with US programmes. The AUKUS submarine deal between Australia, the UK and the US is a particularly striking example of multi-decade industrial commitments. For UK companies like BAE Systems, this represents a meaningful long-term opportunity.

Finally, there is the issue of replenishment. Many Western armed forces have used munitions stocks faster than they can be replaced, and recapitalising those stockpiles has become a strategic priority. The companies that produce shells, missiles and air defence interceptors have therefore moved from cyclical players to centrepieces of national security policy.

The companies in focus

BAE Systems is the UK's flagship defence prime. Its portfolio spans aerospace, naval shipbuilding, submarines, electronics, cyber defence and land systems. With a major presence in the US through BAE Systems Inc and a strong position in Australia and Saudi Arabia, the company is unusually international for a UK industrial. It is also a key partner on flagship programmes including the Eurofighter, the Astute and Dreadnought submarine classes, and the future Tempest fighter project.

Rheinmetall is Germany's defence champion and probably the most-rerated stock in the European sector over the last few years. Its core Business in armoured vehicles, ammunition and air defence has expanded rapidly as European countries place new orders. The company has also moved into newer areas including digital battlefield systems and electric drive technology, helping it pivot to higher-Margin work.

Lockheed Martin is the world's largest pure-play defence contractor. Its products include the F-35 fighter, the C-130 Hercules transport, the THAAD and PAC-3 missile defence systems, and a growing portfolio of space and rotorcraft programmes through Sikorsky and other units. Lockheed's scale and Franchise on programmes like the F-35 give it unparalleled visibility into long-cycle US and allied spending.

Northrop Grumman occupies a slightly different niche, with particular strengths in stealth aircraft, space systems and strategic deterrence. The B-21 Raider next-generation bomber, the Sentinel intercontinental ballistic missile programme and a major presence in space launch and satellites position the company at the heart of US strategic capabilities. While slightly smaller than Lockheed, it carries some of the most strategically important programmes in the US arsenal.

Why this matters now

Defence spending is set apart by visibility. Once a major programme is signed, revenue tends to flow over many years and is largely insulated from typical economic cycles. That makes defence companies an unusual blend: cyclical exposure to political and budgetary trends, but with multi-year revenue stability that resembles utilities or infrastructure once contracts are in place. In an environment of slowing global growth, that combination is attractive to many investors.

Income is the second reason this matters. Most major defence companies have a long tradition of progressive dividends and substantial buy-backs, supported by relatively predictable cash flows. While defence yields are not always headline-grabbing, the combination of Yield, modest growth and Capital returns has historically delivered competitive total returns through the cycle.

Third, ESG is finally evolving in a way that affects the sector. While some funds still exclude defence on principle, others have begun to recognise the role of legitimate defence in supporting democratic societies. Sovereignty, Supply chain reliability and security of Europe have become themes that responsible investors are willing to engage with rather than reflexively avoid. That broader investor base could support valuations over time.

By the numbers (FT Global 500)

Looking at the supplied FT Global 500 figures, BAE Systems is quoted at 20.34 in sterling terms, with a 52-week range of 15.88 to 23.60. The yield is listed at 1.78% and the P/E ratio at 29.57, on a Market Value of 61.24 billion. That valuation reflects BAE's transition from steady industrial to growth defence stock, and the share price now sits considerably closer to its 52-week high than its low.

Rheinmetall is shown at 1,355.80 euros, with a 52-week range of 1,309.80 to 2,008.00. The yield is 0.85% and the P/E ratio is a striking 82.12, on a market value of 63.27 billion. Even after a recent retreat from the upper end of its range, Rheinmetall trades on a multiple that prices in considerable continued growth. The supplied range itself is a useful illustration of just how much the market has moved on the name.

Lockheed Martin is listed at 517.97 in US dollar terms, with a 52-week range of 410.11 to 692.00. The yield is 2.66% and the P/E ratio is 24.02, on a market value of 119.43 billion. The share price sits closer to the lower end of its 52-week band, partly reflecting concerns about programme execution and budgetary timing.

Northrop Grumman is shown at 579.48 dollars, with a 52-week range of 453.01 to 774.00. The yield is 1.59% and the P/E ratio is 18.13, on a market value of 82.31 billion. Like Lockheed, Northrop has retreated from highs but remains a significant business with major long-cycle programmes.

For broader sector context, the supplied sheet also shows RTX at 176.07 dollars, with a 52-week range of 123.60 to 214.50, yield 1.54%, P/E 32.61, market value 237.11 billion. General Dynamics is at 344.30 dollars, yield 1.85%, P/E 21.36, market value 93.11 billion. Rolls-Royce Holdings, with significant aerospace and defence exposure but a distinctive civil aero engine focus, is included at 11.99 in sterling, yield 0.79%, P/E 17.28, market value 100.52 billion. As always, these are snapshot figures and should be checked against the current market when making any decision.

Growth drivers

Order books are the clearest growth driver. The major primes now sit on multi-year backlogs that should support revenue and margin growth for years to come. Munitions and missile production capacity is being expanded across Europe and the US, often with government support, which should translate into both Volume and pricing Leverage as it comes online.

Programme upgrades and life-extensions are another driver. Existing fighter jets, submarines, ships and ground vehicles are being upgraded with new sensors, electronics, communications and weapons systems. These mid-life upgrades carry attractive margins for prime contractors and their key suppliers.

Space and cyber are increasingly important. Defence has long been about more than tanks and aircraft. Satellites, secure communications, electronic warfare, surveillance and cyber operations now account for a growing slice of defence spending. Northrop's deep heritage in space, BAE's electronics and cyber capabilities, and Lockheed's space systems all benefit from this trend.

Finally, exports. With many allied countries seeking to upgrade quickly, export contracts have become an important pillar of growth. AUKUS, F-35 partner-nation orders, and European demand for German, French, Italian and UK products all expand the addressable market for the major primes well beyond their domestic budgets.

Risks to watch

Political risk is the most obvious concern. Defence budgets can be cut as well as raised, and political shifts on either side of the Atlantic could change the rate of growth in spending. The US Debt ceiling, European fiscal rules and changes of government in major countries all introduce uncertainty.

Programme execution is another significant risk. Defence projects are notoriously prone to delays, cost overruns and technical setbacks. Investors have seen this many times before across both US and European programmes, and writedowns can dent Earnings for several quarters at a time.

Valuation risk is increasingly relevant. Rheinmetall's reported P/E of 82.12 in the supplied data is an obvious example of a multiple that requires sustained, high growth to be justified. BAE Systems' P/E of 29.57, while less extreme, is still well above where the company has traded for much of its recent history. If growth assumptions are dialled back, share prices could face renewed pressure even if absolute order books remain healthy.

Reputational and ESG risk has not vanished simply because attitudes have shifted. Some investors and customers still apply strict exclusion policies, particularly around certain weapons categories. Companies that find themselves linked to controversial conflicts or alleged misuse of equipment can face reputational damage even where the underlying products are legitimate.

Finally, there is the risk that orders take longer to convert into earnings than the market currently expects. Building new munitions plants, hiring skilled workers and qualifying complex new systems takes time. The political appetite for spending is real, but the ability of the supply chain to absorb that spending is finite.

Investor takeaway

Defence stocks have moved from quiet corner to centre stage. The structural drivers, sustained European rearmament, US strategic competition with China, replenishment of munitions and modernisation of legacy equipment, are unlikely to fade quickly. That gives the sector a long-cycle growth runway that has not been seen since the early 2000s.

However, valuations now embed many of those positives. BAE Systems and Rheinmetall, in particular, trade on multiples that require disciplined execution and continued political support. Lockheed Martin and Northrop Grumman, while more modestly valued, are exposed to the rhythms of US defence budgeting and programme management. RTX and General Dynamics offer additional flavours, and Rolls-Royce a hybrid civil aerospace and defence story.

For UK retail investors, defence is therefore best treated as a core thematic exposure within a diversified portfolio rather than a short-term punt. Position sizes should reflect both the structural opportunity and the elevated multiples. Diversifying across geographies, products and parts of the value chain, primes, suppliers, electronics specialists, can help smooth out the impact of any individual programme setback. As ever, current share prices should be checked against the supplied snapshot, and any significant decision should be informed by your own broader research.