Last week, the U.S. Senate Armed Services Committee approved this year’s proposed National Defense Authorization Act. For Israel, this would ordinarily not be any reason for worry; close cooperation between defense establishments and alignment of regional interests usually guarantee a good or neutral outcome for Israel in bipartisan defense measures.

Not this time. According to a report from Amir Tibon and Amos Harel of Haaretz, the committee approved language conveying alarm over China’s increasing investments in Israel, including a 25-year contract to operate a port in Haifa starting in 2021. Notably, the proposed language specifically cited national security concerns in objecting to Sino-Israeli partnerships; the U.S. Navy’s Sixth Fleet often docks in Haifa.

If we consider the volume of op-eds and conference speeches as evidence, we would undoubtedly conclude that the central uncertainty of the U.S.-Israel alliance is the Democratic Party foreign policy elite’s willingness to hew to traditional bipartisan support for Israel in the face of continued occupation in the West Bank. While this is still an important consideration, rising tensions between the U.S. and China could eventually put Israel in an uncomfortable position with both parties.

Israel’s relations with Beijing have long been a complicated affair. Despite being the first country in the region to formally recognize the People’s Republic of China in 1950, Israel’s strained relations with the Arab world collided with China’s ambitions to lead a bloc of Third World and developing countries during the height of the Cold War. The Chinese were often willing to meet with Israelis, especially officials from the the Israeli Communist Party before they sided with the U.S.S.R. against Mao in the 1960 Sino-Soviet schism, but it was evident early on that diplomatic ties were not on the table. After Israel’s brief period of non-alignment ended after the breakout of the Korean War, its alliance with the United States complicated matters further (for those interested in the details of early efforts at forging a relationship between the two countries, I highly recommend a fascinating new book, China and Israel, by Professor Aron Shai of Tel Aviv University).

This slowly started to change in the 1980s following American rapprochement with China and the Camp David Accords between Israel and Egypt. Diplomatic relations were finally established with the momentum of the Madrid peace conference in 1991. Commercial ties quickly followed, including significant Israeli sales of weapons to the Chinese military. Understandably, even with the end of the Cold War, this was still worrying for the U.S. In his 1999 eponymous report for a House Select Committee, Rep. Christoper Cox (R-CA) publicly expressed concern about American military technology being “re-exported” from Israel to China. In 2001, the U.S. successfully pressed Israel to cancel a sale of an Airborne Warning and Control System (AWACS) to China. Similar episodes over the next 18 years demonstrated America’s willingness to prevent Israel from forming extensive defense ties with China.

If the U.S. is indeed headed toward a Great Power clash with China, Israel’s commercial relationship with China can also become a source of strain. To be clear, this will not mean a sudden rupture between the U.S. and Israel; as we have seen in the last few months, not every U.S. ally shares its anxieties about China. In April, reports suggested that Britain would allow Chinese technology giant Huawei to build “non-core” aspects of its 5G network. The Bolsonaro government in Brazil is also ready and willing to do business with Huawei.

Still, the closeness of the U.S.-Israel relationship will be tested in unprecedented ways if the latter pursues closer ties with China in the coming decades. In his trip to Britain last month, President Trump, echoing career government and military officials, warned that the increasingly prominent role of Chinese technology firms could threaten American intelligence sharing with the country. If this was the American position toward a fellow member of the Five Eyes intelligence alliance, it is easy to imagine a tougher line being taken on an ally with whom it has an historically less trusting intelligence relationship.

Israel should tread carefully. Whatever political and economic benefits it can gain from China are tiny in comparison to the importance of its strategic alliance with the U.S. (a term which China refuses to apply when it comes to Israel). Non-alignment or playing both sides in a delicate balancing act is perhaps consistent and feasible for some American allies, but not ones with whom it has a “special relationship” valued in both major parties.

There may be some logic to a small country like Israel diversifying its collection of alliances, but growing bipartisan animosity toward China in the U.S. should be the determining factor here. Israel is heavily integrated in the American-led international financial system, where the rule of law and not the whims of the Politburo Standing Committee traditionally prevails. Its technology sector’s most lucrative partnerships are with Silicon Valley, not the uncompetitive and heavily subsidized behemoths in China. The largest Jewish diaspora population is in the U.S.

In the 1950s, Israel sided with the United States in the the last Great Power competition. It would be wise to do so again without reservation.