The Trump administration’s antipathy toward arms control will strike again on November 22, when the United States withdraws from the Open Skies Treaty. That is a mistake. While Russia has violated the treaty, the United States has reciprocated. NATO allies support the treaty — which focuses first and foremost on enhancing European security — and wish the United States to remain a party.

Whether the treaty can continue following the American departure remains to be seen and will depend on what Russia does. When it takes office, the Biden administration should consider reentering the agreement, though that may require some creative international lawyering.

The treaty

The Open Skies Treaty, which entered into force in 2002, permits countries to fly unarmed aircraft with cameras and other sensors over the territory of the treaty’s other 34 members states. Based on an idea advanced by Dwight Eisenhower in the 1950s, Open Skies provides for the collection of imagery of military installations and activities in order to foster transparency.

Each party to the treaty has two annual quotas: the number of flights it may conduct over other treaty-parties (active quota), and the number of overflights that it must accept (passive quota). Aircraft are inspected before conducting an Open Skies flight, and personnel from the country to be overflown are on board during the flight.

The treaty offers several advantages. While the capabilities of U.S. reconnaissance satellites are superior to those of Open Skies aircraft, all 34 treaty-parties have access to imagery from the flights (whereas satellite imagery is highly classified). The treaty gives U.S. allies and partners, who lack sophisticated imagery satellites, the opportunity to gather confidence-building data. Moreover, aircraft offer greater flexibility than satellites in flight plans and can fly under cloud cover. Open Skies flights can also be used to send political signals: After Russia instigated the conflict in Donbas in 2014, for instance, the United States targeted flights at eastern Ukraine and the bordering Russian territory in order to send a message of U.S. support for Kyiv.

By 2019, the 34 parties had conducted a total of more than 1,500 overflights. During the treaty’s first 15 years of operation, the United States conducted 196 flights over Russia and Belarus (the two are paired for treaty purposes), while Russia conducted 71 flights over the United States.

Unfortunately, Russia has violated the treaty by imposing restrictions on certain flights over its territory. In response, the United States imposed reciprocal restrictions on Russian flights over U.S. territory. While the Russian violations are problematic, Washington has not declared that they constitute a material breach — that is, a violation that vitiates the central purpose of the treaty. Nevertheless, on May 21, Secretary of State Pompeo released a statement saying that, unless Moscow returned to full compliance, Washington would leave the treaty in six months’ time. The U.S. government provided formal notification of its intention to withdraw to the other treaty parties the following day; hence, the U.S. withdrawal will take effect on November 22.

A serial killer of arms control?

By all appearances, the Trump administration sees little value in arms control and nonproliferation arrangements. In 2018, President Trump decided to withdraw from the 2015 Joint Comprehensive Plan of Action that limited Iran’s nuclear capabilities. Iran can produce the fissile material for a nuclear bomb in a much shorter time today than three years ago. Meanwhile, the United States stands isolated, with close allies such as Britain, France, and Germany staying in the agreement and ignoring Washington’s requests to apply sanctions on Tehran.

In 2019, the Trump administration withdrew from the 1987 Intermediate-range Nuclear Forces Treaty, an agreement signed by Ronald Reagan and Mikhail Gorbachev that banned an entire class of missiles. Russia had violated the agreement by deploying a prohibited missile, but President Trump’s team showed no interest in preserving the treaty, eschewing military and political measures that could have pressured Moscow to return to compliance.

In 2020, administration officials reportedly considered conducting an underground nuclear test. That would violate a long-standing test moratorium observed by the United States, Russia, China, Britain, and France (the Comprehensive Test Ban Treaty, which would prohibit all nuclear tests, has not entered into force). A U.S. nuclear test would open the door to tests by others, eroding the nuclear knowledge advantage the United States enjoys from having conducted more tests than the rest of the world combined.

Happily, the 2010 New Strategic Arms Reduction Treaty (New START) appears safe. True, the Trump administration could in its final days give notice of an intention to withdraw, but the intention could only be carried out three months later. President-elect Biden supports New START and supports its extension; he would revoke any such notice.

However, Open Skies looks to be the outgoing Trump administration’s next — and last — victim.

What next for Open Skies?

The Open Skies Treaty focused on strengthening confidence and security in Europe, one reason why the Trump administration should have given the views of its allies greater weight. A major question now turns on what Moscow will do, given that the U.S. departure will mean that Russia can conduct flights over European territory and Canada but not the United States.

If Moscow decides to withdraw from Open Skies, perhaps citing the treaty’s decreased value because it can no longer overfly American territory, the treaty will collapse. NATO allies will see little point in overflying other allies or partners such as Sweden and Finland. Alternatively, Moscow could decide to remain in the treaty, at least for a time, in part to score propaganda points over the U.S. withdrawal.

At a November 12 press conference, Russian Foreign Minister Sergei Lavrov said that, if the treaty continues to operate, Russia would insist that, when conducting flights over other treaty-parties, its aircraft could overfly and take pictures of U.S. bases and facilities located on their territory. Lavrov added that countries remaining in the treaty would have to commit not to transfer Open Skies imagery or other data to the United States.

His demands do not appear unreasonable. The treaty makes no provision for a country to deny another treaty-party the ability to fly over U.S. facilities on its territory, and the treaty provisions provide that imagery and other data gathered from overflights shall be shared only with other treaty-parties. These conditions will put U.S. allies in Europe in an awkward position — something that Lavrov no doubt relishes.

If, however, the treaty can be sustained into 2021, the Biden administration could consider reentering. The advantages offered by the treaty remain valid, despite Russian violations.

Doing so, however, could require creative work by international lawyers. Were Washington to re-sign the treaty, it then would have to resubmit it to the Senate for consent to ratification. However, with at best 50 Democratic senators (assuming far-from-certain wins in both of the Georgia run-off races), consent to ratify would still need 17 Republican votes. It is difficult to see that many Republicans consenting to ratify a treaty from which a Republican administration has just withdrawn.

Alternatively, the Biden administration could consider rejoining the treaty on the basis of an executive agreement, perhaps one approved by simple majorities in the House and Senate. Such a mechanism would require the agreement of the other 33 treaty-parties. Hopefully, the Russians would not choose to be spoilers.

When it takes office, the Biden administration should seek to rejoin Open Skies. The treaty serves U.S. interests. That is what NATO allies want. And within the treaty, Washington can push to get Russia back into compliance while continuing restrictions that deny Russia the full benefits of overflying the United States. The new administration should make clear its intention to rejoin the treaty and put some clever lawyers to work figuring out a way to make that happen.