In recent years, the U.S.-Japan alliance has drawn dramatically closer. This is mainly driven by mutual fear of China’s rise and intentions especially in regard to Taiwan, shared concern about East Asian shipping routes, and the North Korean nuclear weapons program. Now, however, some defense experts fear the outcomes of current elections in either or both countries could make alliance cooperation more difficult and even change the trajectory.

The Japanese lower house snap elections, taking place on Oct. 27, could well affect security-minded new Prime Minister Shigeru Ishiba’s standing and determine how long he will remain prime minister or even if he will. The U.S. elections on Nov. 5 are also expected to have consequences for the tone of the relationship, if not its existence.

Japan and the U.S. have compatible Free and Open Indo-Pacific policies. They have ramped up security cooperation: support for Third Countries, new minicoalitions with three or four partners, participation in military exercises, and defense and cyber technology partnerships. For Japan, the U.S. alliance is almost existential; for the U.S., Japan is pivotal to the U.S. defense effort in the Pacific and even Indian Ocean, and the largest foreign global host of U.S. troops.

Ishiba became prime minister because his predecessor, Fumio Kishida, threw in the towel after his approval plunged because of a party slush fund scandal.

Although considered a gadfly, Ishiba barely won the ensuing contested internal party election in the second round because it was thought he would enjoy more public support than his main rival. He also has pledged to continue and strengthen the current direction of the alliance, including increased Japanese defense spending, cooperation with neighbors to the south, and a close relationship with South Korea. In the past, Ishiba even mused about creating an Asian NATO, but since this is not realistic, he has dropped mention of it.

The election in Japan on Sunday is a calculated gamble. By leading his Liberal Democratic Party to victory, Ishiba hoped to gain legitimacy against party rivals while improving the LDP’s public standing. Neither prospect looks bright. Ishiba’s decision to drop party endorsement for some scandal-tainted parliamentarians was more show than sanction, perhaps just enough to outrage his party opponents, but not enough to impress the public.

Some polls suggest that the LDP and its Komeito coalition partner could lose 50 seats or even their majority, requiring them to scramble for a new partner. This raises the prospect that Ishiba’s tenure will be short and that Japan may embark on a period of revolving-door, weak leadership. This would draw attention inward and make Japan a less stable alliance partner.

The U.S. presidential election is another concern in Japan. Allies generally seek stable, predictable U.S. leadership and thus usually prefer continuation of the party in power. While the U.S.-Japan alliance was relatively unscathed during the previous Trump administration, the former president’s apparent emphasis on fairer burden-sharing over mutual security priorities added stresses.

The LDP leadership also favors greater sharing of the alliance burdens, but they fear U.S. expectations will exceed their political capacity to deliver. Personalistic policy gyrations in the Trump period toward China and North Korea were also disturbing for Japan’s more bureaucracy-driven foreign policies.

Given the basic security anxieties and priorities of the two countries, election outcomes will certainly not result in abandonment of the alliance. But they could well add stress and uncertainties, slowing the pace of enhanced cooperation just as military leaders and the new political leaders of both countries grapple with a rapidly changing security environment.

Charles E. Morrison is a former president of the East-West Center and current senior fellow.