To counter China in Southeast Asia, take Indonesia seriously

The news that Russia is seeking to station air-force planes in Indonesia was sensational, instantly denied and almost certainly true. Although it’s a characteristically murky tale, it carries lessons that the Trump administration should note.

One is that the U.S. is unlikely to win the strategic, military, economic or technology competition with China unless it has a strong position in Southeast Asia. Another is that the China-Russia alliance is tighter than ever, and it’s increasingly global. A third is that if you want to understand Beijing’s strategic policy in Asia today, you should look to the geography of Japan’s military campaigns in World War II.

The open-source military and security website Janes.com first reported a Russian request for use of the Indonesian Manhua air-force base, on Biak island in the remote Indonesian province of Papua. The story caused a stir in Australia because Biak is only 850 miles from Darwin, with its substantial U.S. military presence. Australia’s Defense Minister Richard Marles reported that his Indonesian counterpart, Sjafrie Sjamsoeddin, told him the report was untrue. But don’t be reassured.

Indonesia is a nation of 290 million. It proclaims fidelity to the Non-Aligned Movement, so a permanent foreign base on its territory is extremely unlikely. Like all giant nations—its population is smaller only than India, China and the U.S.—Indonesia can be somewhat self-obsessed. It’s the giant of Southeast Asia. Under President Prabowo Subianto, a former general and defense minister who was for some time banned from entering the U.S. on human-rights grounds, Indonesia has grown much closer to Russia. Like New Delhi, Jakarta is strategically promiscuous. It signed a defense agreement with Australia, but Russia is its biggest military supplier.

Shortly after he was elected, Mr. Prabowo went to see Vladimir Putin in Moscow. Military cooperation was high on the agenda. Mr. Prabowo took Indonesia into the Brics grouping of Brazil, Russia, India, China and South Africa. Indonesia opposed the trilateral Aukus agreement, which will see Australia acquire nuclear-powered submarines.

Indonesia and Russia engage in substantial trade in commodities. Russia has sought a presence in Southeast Asia for some time, looking unsuccessfully to revive elements of its old alliance with Vietnam. While it won’t get a permanent base in Indonesia, there are other ways Moscow could secure an enhanced military presence there. It has, for example, based air-force planes in Biak in the past.

We in Australia know something of hosting allied forces without establishing a foreign military base. Pine Gap, in Australia’s Northern Territory, is one of America’s most important signals-intelligence stations. It’s a joint U.S.-Australian facility, not technically a U.S. base. Similarly, U.S. Marines, ships and planes rotate through Australia.

It’s likely the presence of such U.S. forces in Australia is an important part of Russia’s thinking regarding Indonesia. Russia’s ambassador in Jakarta, Sergei Tolchenov, responded to the air-base story with a statement confirming that military cooperation is at the heart of Indonesia-Russia relations. But these are purely bilateral, he said, not aimed at any third country. He also claimed, preposterously, that U.S. forces in Australia were the real military risk in the region, especially U.S. missiles that could hit Indonesia and other Association of Southeast Asian Nations countries.

Why would Russia pick a verbal fight with the U.S. in Australia and Indonesia, when Mr. Putin is performing the dance of the seven veils with President Trump over Ukraine? One reason would be to oblige Beijing.

Xi Jinping has been on a tour through Vietnam, Malaysia and Cambodia. His message in the wake of the Trump administration’s erratic tariff performance is that Beijing is a more reliable partner than Washington. This complements Beijing’s efforts to gain military presence and leverage throughout the region. Most Southeast Asians are scared of China and want the U.S. to balance its influence. But, with the exception of Singapore, they’re all either poor or middle-income nations. The Trump tariffs were a huge shock, and more than anything ran against the stability the U.S. once represented.

China’s presence in Indonesia is complicated by the past persecution of ethnic Chinese there, and the association with Indonesian communism in the 1960s. Russia doesn’t have that baggage. It could possibly wrangle an occasional, even a regular, military presence. Indonesia and Russia conducted their first joint maritime exercises in November.

Finally, recall the geography of Japan’s Pacific war. It was fought in Southeast Asia and in the islands of the South Pacific. Beijing has tried repeatedly to sign security agreements with Pacific islands nations such as the Solomon Islands and Vanuatu. U.S. and Australian intelligence take it as given that Beijing wants a military base in the South Pacific.

China’s military presence, supplemented now by Russia, threatens U.S. forces in the region and increases Beijing’s ability to intimidate, coerce and influence other nations. For American allies like Australia that’s bad news. It’s bad for the U.S. as well.

A U.S. military presence, a respectable trade agenda and the continuation of the civic virtues with which the U.S. has traditionally inspired the world, would win Southeast Asia for Uncle Sam. Indonesia is the biggest nation about which Americans know the least, yet its influence has been substantial. For Washington to lose that influence would be tragic, unnecessary and dangerous. But it would make Russia—and China—very happy.

Mr. Sheridan is foreign editor of the Australian.