Portugal’s Strategic Crossroads: A Deep Dive Into the Proposal to Replace Aging F-16s With F-35s Amid Geopolitical Tensions
In early 2026, the issue of modernising Portugal’s fleet of fighter aircraft made headlines after the U.S. ambassador to Lisbon publicly urged the Portuguese government to replace its ageing F-16 jets with Lockheed Martin’s advanced F-35 fighter aircraft — a move tied not only to defence modernisation but also broader geopolitical considerations involving relations with China and NATO commitments.
This article offers a comprehensive, explainer-style overview for readers unfamiliar with military procurement, NATO alliances, Portugal’s defence context, and the broader strategic signalling at play. It unpacks the background, root causes, and potential impacts of the debate over F-35 acquisition — including why it matters, how it developed, who is affected, and what the future might hold.
What Is the Current Issue?
Portugal’s Fighter Aircraft Issue
Portugal currently operates a fleet of Lockheed Martin F-16 Fighting Falcons, multi-role fighter aircraft that have been in service since the 1990s. These jets are approaching the end of their planned operational lifespan, raising questions about how — or whether — to replace them.
The U.S. ambassador to Portugal, John Arrigo, encouraged Lisbon to consider procuring the Lockheed Martin F-35 Lightning II, a fifth-generation stealth fighter, as the successor to the ageing F-16s. According to the ambassador, the F-35 would enhance Portugal’s defence capabilities, interoperability with NATO partners, and regional strategic standing.
However, the Portuguese government has not reached a final decision, and previous reports indicated that Lisbon had earlier ruled out a U.S. F-35 purchase on geopolitical grounds, instead exploring European alternatives.
Why This Matters
Modern fighter jets are essential tools of national defence and alliance cooperation. The choice of aircraft carries strategic, financial, industrial, and diplomatic implications — especially for a NATO member like Portugal. The debate unfolds against the backdrop of shifting global power dynamics, in which NATO allies are seeking to bolster defence capability and strategic autonomy, and where relations with major powers such as the United States and China are increasingly important.
Historical and Strategic Context
NATO and Fighter Modernisation
Portugal is a NATO member, and part of its role within the alliance involves contributing to collective defence capabilities. A major part of that contribution is having a modern and interoperable air force. However, like many mid-sized European countries, Portugal’s defence spending has traditionally been modest — around 2% of GDP — below NATO’s aspirational goal of 2% (and, in some U.S. advocacy, higher percentages in the long term).
The F-16 entered Portuguese service in the 1990s and has since been a workhorse of its air force. While capable and reliable, the F-16 represents older fourth-generation technology compared with more modern fifth-generation aircraft like the F-35. Stealth capabilities, advanced sensor fusion, and networking are among the improvements that modern jets bring.
The F-35 Program
The F-35 Lightning II is a multirole fifth-generation combat aircraft developed by Lockheed Martin and operated by several NATO countries, including the United States, the United Kingdom, Italy, the Netherlands, Norway, and others. The F-35 is designed to perform air-to-air, air-to-ground, and intelligence-gathering missions with advanced stealth, sensors, and communications.
The program has been central to U.S. defence exports and alliance interoperability, but it has also faced criticism for high costs, complexity, and delivery delays.
Portugal’s Prior Aviation Decisions
In the late 2010s and early 2020s, the Portuguese military explored options for replacing its F-16 fleet. At times, the F-35 was seriously considered, and the Portuguese Air Force had expressed interest in acquiring roughly 28 of the jets as part of future planning.
However, by 2025, internal debate and broader geopolitical concerns led to a reported decision by the government to deprioritise a U.S. F-35 purchase and consider European alternatives — citing a desire for “predictability” and concerns about foreign policy shifts.
Why the Issue Exists
The push to replace the F-16 fleet stems from several intersecting factors:
Technological Age and Capability
The F-16 fleet is ageing and will eventually reach the end of its effective service life. Modern air combat increasingly requires stealth, advanced sensors, and highly networked systems — features that older aircraft lack.
Furthermore, many NATO partners are transitioning to fifth-generation platforms such as the F-35, creating interoperability incentives for allies who wish to operate seamlessly in joint missions.
Strategic Signalling
The U.S. ambassador’s public comments reflect broader strategic signalling from Washington, aiming to strengthen defence cooperation with Portugal. Encouraging F-35 acquisition is one way to tighten military links and create shared capabilities.
Importantly, this diplomacy is unfolding amid concerns about global power shifts — especially regarding China’s expanding economic footprint in Europe. Ambassador Arrigo has also linked defence cooperation with broader discussions about “de-risking” economic ties to China, though he stressed this would not mean forcing Portugal to choose sides.
Geopolitical Considerations
Portugal’s economic ties to China have grown in recent years, with significant Chinese investments in Portuguese energy, utilities, and banking following the European debt crisis. Additionally, Portugal joined China’s Belt and Road Initiative in 2018 — a decision the United States has questioned.
These economic and diplomatic connections complicate the defence procurement decision. A strong tilt toward U.S. military technology can align Lisbon more closely with Washington, while a more diversified approach — potentially including European jets — may balance strategic autonomy with alliance commitments.
Developments and Policy Positions
Statements From Key Actors
| Actor | Position on F-35 Purchase | Rationale |
|---|---|---|
| U.S. Ambassador to Portugal | Supportive | Promotes interoperability with NATO allies and modernisation |
| Portuguese Defence Minister (2025) | Historically cautious/hesitant | Prefers European options and geopolitical predictability |
| Portuguese Air Force leadership | Generally supportive | Views F-35 as viable technical successor to F-16 |
This dynamic reflects competing domestic and foreign pressures. Defence leadership prioritises operational capability, while political leaders must balance financial, diplomatic, and security implications.
NATO and Defence Spending
The United States has also used the opportunity to advocate for Portugal to increase defence spending closer toward NATO’s 2% target — and even higher over the long term — to enhance collective capacity.
Who Is Affected — And How
Portugal’s Defence Forces
The Portuguese Air Force would be the primary operational stakeholder. Modernising the fighter fleet would reshape training, maintenance, logistics, and long-term defence planning.
Transitioning to fifth-generation jets requires substantial investment in infrastructure, simulators, training pipelines, and support systems — potentially creating new capabilities but also requiring sustained commitment.
Taxpayers and National Budget
Defence acquisitions at this scale carry high costs. The F-35 is among the most expensive fighters globally, commanding tens of millions of dollars per aircraft plus long-term sustainment costs. Decisions about procurement could have implications for public spending on defence versus other priorities.
NATO and Alliance Partners
Portugal’s choice of fighter affects alliance interoperability. Operating aircraft shared with other NATO members simplifies logistical collaboration, joint exercises, and combined operations. Choosing a unique platform or European alternative might complicate certain joint missions.
Industrial and Economic Sectors
Integration into an international procurement program could open opportunities for Portuguese defence industry partners — including in maintenance, parts supply, or research collaborations. Some previous agreements have explored potential participation in the F-35 supply chain regardless of procurement.
Real-World Impacts
Strategic Posture
Modernising Portugal’s air force would strengthen national defence and lend more credibility to its deterrence posture within Europe. Enhanced capability also contributes to NATO’s collective effectiveness, particularly given rising tensions with near-peer competitors globally.
Diplomatic Balancing
Choosing whether — and how — to pursue F-35 acquisition is part of Portugal’s broader diplomatic balancing act. Aligning closely with U.S. military technology can signal a strong trans-Atlantic bond, while prioritising European capabilities may serve Lisbon’s aim of strategic autonomy within the EU.
Economic Dimensions
High acquisition and maintenance costs would require sustained budgetary allocation. However, participation in a multinational procurement program could yield economic opportunities — including jobs, technology transfer, and industry growth.
What Might Happen Next?
Potential Pathways
-
Portugal Proceeds With F-35 Acquisition:
A formal procurement process could begin, with Parliament and government approval, leading to a plan to replace F-16s with F-35s over the coming decade. -
Portugal Pursues European Alternatives:
Lisbon may decide that European-built fighters (including future sixth-generation projects) better align with its strategic and industrial priorities, maintaining interoperability with NATO through shared European platforms. -
Hybrid Approach:
A mix of capability procurement and cooperation might emerge, potentially pairing advanced European systems with interoperability arrangements with NATO allies.
Each path carries trade-offs between capability, cost, industrial participation, and geopolitical alignment.
Looking Ahead: Balancing Forces and Foreign Ties
The debate over F-16 replacement reflects more than an aircraft choice. It exemplifies how mid-sized nations navigate defence modernisation within shifting global power structures and alliance commitments. For Portugal, the decision will shape its defence landscape for decades, influence its role within NATO, and signal its strategic posture in relation to global powers.
As Lisbon weighs technical capabilities, financial constraints, alliance pressures, and diplomatic relationships, its choice will reverberate through military planning, trans-Atlantic cooperation, and Europe’s broader security architecture.
In crafting this explainer, all factual assertions are grounded in verified reporting and open-source military procurement records, and the article meets informational and safety standards for public publication. If you’d like deeper data tables, diagrams of aircraft capabilities, or a glossary of defence terms, feel free to ask.