Entering service from 2014, when the F-35B platform first joined the U.S. Marine Corps, over 3000 of the Lockheed Martin F-35 are expected to be built over a decades-long production run, and while the fighter is still far from ready for medium or high-intensity combat it has the potential to be a highly capable aircraft once current performance issues are solved. The aircraft was designed as a lighter and cheaper counterpart to the F-22 Raptor

heavyweight twin-engine fighter, and while the Raptor was reserved for the U.S. Air Force alone the F-35 is being widely offered for export. The F-35 is being produced on a much larger scale today than any other class of fighter in the world, with the exception of the Russian Flanker design which has multiple production lines open in Russia, China, and India simultaneously in a number of variants. Considerable foreign interest in the F-35 has led to it being operated by over a dozen countries, including partners in development such as Britain and Denmark, and clients for export such as Israel and Belgium. With production lines expected to be expanded further, and the cost of the fighter decreasing due to the benefits of economies of scale which is expected to allow it to price rival Western designs out of the market, a number of new clients for the aircraft are expected to place their first orders over the coming years. A look at the five leading potential clients for the F-35 is given below.

 
United Arab Emirates

The United Arab Emirates has shown a strong interest in acquiring the F-35A since long before the platform entered service in the U.S. Air Force itself. The Gulf State has most closely modeled its military along Western lines and was the second in the world to deploy ‘4+ generation’ F-16 Fighting Falcons equipped with AESA radars after Japan - with the Emirati jets developed under the F-16E program. There have been a number of strong arguments both ways regarding whether the U.S. should provide the Arab state with the F-35, and while strengthening a leading regional partner and gaining revenues from arms sales have made a sale attractive, Washington has come under Israeli pressure not to provide any Arab state with stealth fighters. The F-35s extreme reliance on an American centered network, however, and it's high maintenance requirements and needs for a near-constant supply of spare parts, means the U.S. would have little trouble grounding the UAE's fleet should Abu Dhabi ever seek to use the jets in a way that contravenes American interests. In addition, variants with downgraded software similar to those previously set for export to Turkey are expected to be sold to the UAE to further reassure Israel. These factors, combined with the benefits of having F-35s stationed so near Iran, where their sensors will likely pick up a great deal of valuable intelligence, are expected to prevail over Israeli concerns.

 
F-35 and F-16 Single Engine Fighters

Taiwan

Taiwan was a leading client for the F-35’s third and fourth generation predecessors, the F-5E and F-16, producing over 300 of the former under license and upgrading the latter domestically from the F-16A to the F-16V standard. Taiwanese efforts to acquire the F-35 have notably been blocked by the U.S. - primarily due to concerns of strong sentiments supporting the Chinese mainland among Taiwan’s population meaning many of the stealth jet’s technologies could be compromised through espionage. The possibility of reunification between Taiwan and mainland China, meaning the F-35 would effectively be placed in the hands of the Chinese People’s Liberation Army much as F-5Es and other advanced American hardware were placed in North Vietnamese hands after reunification in 1975, has also deterred the U.S. from making such sales. Taiwan has thus made do with access to the F-16V, not only upgrading its F-16s to this standard but also purchasing 66 new F-16s from the U.S. This has made Taiwan by far the largest foreign client for the F-16V and has been vital to keeping F-16 production lines open after more than 40 years.

Taiwan is expected to persist in its efforts to acquirers the F-35, with the F-35B which has advanced vertical landing capabilities being particularly valuable for its ability to operate from island outposts which have only short or makeshift runways. As the F-35’s technologies become less sensitive, and the U.S. comes closer to fielding its first sixth-generation fighters, the possibility of a sale to Taiwan will grow. With the U.S. Military retaining a growing presence on the territory, this will help to ensure the fighters are secure. It has been speculated that the U.S. only denied Taiwan the F-35 to gain a new client for the F-16 - which had seen very low foreign demand at the time - meaning an F-35 sale after the F-16 contract is complete remains a significant possibility.

 
F-35 Fifth Generation Fighters 'Elephant Walk'

Switzerland

The Swiss Air Force currently fields a small number of F-5E and F-18 fighters, both of which are scheduled for retirement in the coming years and are expected to be replaced by a ‘4+ generation’ or 5th generation fighter. While only Western fighter designs have been considered, Switzerland is likely to look to purchase American aircraft which has a long history of operating, with the F-35A considered the leading contender over European rivals such as the Eurofighter and Rafale. The F-35’s higher operational costs, which make it much more expensive to operate than the F-18 or the F-5, mean the Swiss Air Force could be dissuaded from making such an investment, although the benefits the F-35 could provide and the fighter’s prestige still make it a highly attractive option. Unlike other potential operators, Switzerland is unlikely to seek to operate the F-35 alongside the fleets of other countries or alongside other advanced aircraft, meaning the uses of the jet's highly valued data links and network-centric warfare capabilities will be limited. 

 
Su-35 Heavyweight Fighters

Indonesia

Indonesia could become the second client for the F-35 in Southeast Asia after Singapore, following considerable Western pressure on the country including threats of economic sanctions to cancel its contract to acquire 11 Su-35 fighters from Russia. Indonesia currently operates F-16, F-50, SU-27, and SU-30 fighters, but offering the F-35 combined with threats of economic sanctions and diplomatic pressure could press the country to shift towards a fully Western air force - replacing the planned Su-35s and the two older Russian fighter classes with the American stealth jets. Such a purchase would come after both Australia and Singapore acquired their first F-35 jets, and would increase interoperability with neighboring air fleets as well as with the U.S. Air Force. It would, however, undermine the independence of the Indonesian Air Force, given that its F-35 would likely be downgraded relative to those of its neighbors which have much closer relations with the U.S., and the fact that Washington previously stopped the flow of spare parts to ensure that the Indonesian F-16 fleet was inoperable at a time of high tensions with Australia in the 1990s. A shift away from a diverse fleet which includes both Western and Russian designs is likely to be fiercely debated in Indonesia itself - with the outcome uncertain.

 
F-35 and F-15 Fighters

Qatar

Qatar is the second Arab state to have officially expressed an interest in the F-35, which follows purchases of Rafale, Eurofighter, and F-15QA fighters to provide it with one of the most diverse small fleets in the world. With Doha considered a leading Western partner in the Middle East, which formerly hosted the U.S. Central Command and hosts a considerable U.S. military presence, the risk that F-35s in the country’s hands could undermine Western interests in the region are negligible - not least because of its extremely heavy reliance on the U.S. for security. Sales of the F-35 to Qatar could potentially increase interest in the fighter from other gulf states such as Saudi Arabia and Kuwait, which cut diplomatic ties to Doha in 2017 over its alleged sponsorship of terrorism.