Eric Gomez and Benjamin Giltner

The backlog of US arms sales to Taiwan grew in June 2024 to $20.5 billion, an increase of almost $840 million from the previous month. As shown in Figures 1 and 2, asymmetric capabilities account for the backlog’s growth in June.

June 2024 featured two major developments: the first arms sales under the newly inaugurated Lai Ching-te administration, and the release of a Ministry of National Defense (MND) report to Taiwan’s legislature that provides new information about several delayed arms packages.

For a detailed list of the arms packages in the backlog, see Table 1.

Lai Administration Off to a Good Start

The Defense Security Cooperation Agency (DSCA) announced four new Foreign Military Sales (FMS) cases to Taiwan in June 2024. These arms sales should please advocates of an asymmetric defense strategy for Taiwan as they suggest that the Lai administration is taking asymmetric defense seriously.

The four new FMS cases are split between maintaining Taiwan’s existing traditional capabilities and acquiring new asymmetric capabilities. Traditional capabilities are more flexible than asymmetric capabilities, but are also more expensive to buy and maintain. Though Taiwan’s military has made some progress toward an asymmetric strategy—which offers a better chance of resisting a Chinese invasion attempt—it has generally favored traditional capabilities.

Two of the June arms sales maintain Taiwan’s existing traditional capabilities while the other two acquire new asymmetric systems.

On June 5, the DSCA announced sales of standard and non-standard spare parts for F‑16 fighter aircraft for $220 million and $80 million, respectively. We did not include these two sales in the arms backlog dataset because they maintain existing capabilities that Taiwan could use to protect itself, whereas our dataset covers US weapons that Taiwan does not have yet.

Sales of F‑16 spare parts help Taiwan maintain the aircraft it already possesses, but Washington should not sell Taipei new aircraft. Traditional capabilities, like F‑16s, can conduct a wider range of missions than asymmetric capabilities, but their vulnerability to China’s superior traditional forces makes them less useful in a high-end conflict.

The two June 2024 FMS cases that are included in the backlog comprise a $300 million sale of 291 ALTIUS 600-Ms and a $60 million sale of 720 Switchblade 300s, both of which are loitering munitions—small unmanned aerial vehicles armed with explosives that detonate when the vehicle crashes into a target. Loitering munitions have been used extensively by Ukraine’s military against invading Russian forces. For Taiwan, putting many of these capabilities in the hands of small units gives options for conducting precise attacks, even if Taiwan’s more advanced strike capabilities like aircraft or artillery are disrupted or destroyed.

The State Department is confident that Taiwan will receive these 1,011 loitering munitions by the end of 2025. If this timeline proves accurate, it would be a major success story for a US arms sale to Taiwan.

MND Reports Reveal Significant Delays

A majority of the $837 million increase in the arms backlog comes from adding old weapons sales back to the backlog. Initially, we did not include these items in the backlog, as other sources indicated that these weapons had been delivered. However, two reports from Taiwan’s MND that we located and translated this month indicate that these weapons are, in fact, delayed.

The two MND sources are a June 2024 letter to the Legislative Yuan on the status of five arms sales (three delayed, two ahead of schedule), and an excerpt of a report on the MND’s 2024 budget request published in October 2023. Based on these sources, we added three asymmetric arms sales to the backlog worth a combined $477 million.

In late 2015, the United States announced sales of Stinger man-portable air defense missiles and TOW-2B anti-tank missiles to Taiwan. While SIPRI’s Arms Transfers Database claimed both packages were delivered, Taiwan’s MND said otherwise.

For the Stinger missiles, the October 2023 MND report says there have been multiple issues with both the 2015 sale (250 missiles for Taiwan’s navy) and a later 2019 sale (250 missiles for Taiwan’s army). Bureaucratic issues in the MND created a delay in both programs, requiring a new Letter of Acceptance for the sales, which was signed in 2020.

According to the MND report, delivery of the Stingers was originally supposed to occur in 2020 (navy sale only) but it was revised twice, first to 2022 and then to no later than 2025 (both navy and army sales). According to the Taiwanese press, Taiwan received an initial shipment of Stinger missiles in 2023, but based on the MND report and subsequent press reporting, we assess that neither the 2015 sale nor the 2019 sale have been completely delivered. The October 2023 MND report states that since 2021 Taiwan issued two letters of protest to the United States over delays in Stinger deliveries. The 2015 Stinger sale increases the backlog by $217 million.

As for the TOW-2B missiles, the United States announced a sale of over 750 missiles for $268 million in late 2015 which was revised downward in 2018 to 460 missiles for $131 million. In July 2019, the United States updated this sale, adding 1,240 TOW missiles valued at $241 million for a total of 1,700 missiles and $372 million.

Per the October 2023 MND report, the initial tranche of 460 missiles was supposed to be delivered by 2022, but this was pushed to late 2023. The June 2024 MND letter goes on to say that none of the 1,700 missiles have arrived due to US production delays and issues with pre-shipment quality control testing. Our dataset already included the 1,240 missiles, but not the 460 missile sales. Based on the new MND letter, we have added the smaller sale to the backlog.

Taiwan’s defense minister claimed that all 1,700 TOW missiles will arrive by the end of 2024. Yet the fact remains that Taiwan has not received any of a relatively simple capability first notified to Congress nine years ago.

The final addition to the backlog from the MND reports is a July 2019 modification to a 2015 sale of Javelin missiles and launchers. This modification covers 400 Javelin missiles and 46 launchers valued at $129 million (the 2015 sale was delivered in 2020). According to the October 2023 MND report, Taiwan was supposed to receive the 400 Javelin missiles and 46 launchers by the end of 2022. The June 2024 MND letter clarifies that all the launcher units were delivered, but not all the missiles have arrived. As of June 2024, 251 missiles have been delivered, with the remaining 149 scheduled to arrive by the end of the year.

The Javelin delivery timeline is not as significantly delayed as the Stinger and TOW missiles. However, it was missing from previous versions of our dataset, which we have fixed.

Conclusion

The month of June was a mixed bag for the Taiwan arms sale backlog. The first US arms sales to the Lai administration will advance Taiwan’s asymmetric capabilities, which are essential for effective defense against a Chinese invasion. However, new information from Taiwan’s MND reveals longer delays for several key asymmetric capabilities.

Putting Taiwan in a better position to protect itself from China will require shorter delays in arms deliveries, and US policymakers need to do more to identify and fix the sources of delays.

Taiwan Arms Backlog Dataset, June 2024