In March of 2014, Russia annexed Crimea, a small peninsula, located on the southern end of Ukraine, that extends into the Black Sea.

The incursion into Ukrainian territory was a flagrant effort on Vladimir Putin’s part to subvert Western influence in the Ukrainian state. The move can also be considered a harbinger for a larger Russian endeavor to reassert its influence over former Soviet states or to incorporate them into the Russian Federation.

As the Russian journalist Leonid Bershidsky notes in Bloomberg View:

Throughout the conflict, Putin has never been constrained by any threat of Ukrainian pushback. He doesn’t want overt control of this or any neighboring country, just political and economic influence. In Ukraine, he wants to cripple the country enough that the West will be wary of taking it in, integrating it into European institutions. So far, that plan is working: Ukraine remains destitute and riven by internal strife.

In 1991, Ukrainians overwhelmingly (92%) voted for independence. Fast forward twenty-five years, and on the heels of a Donald Trump presidency in the U.S. and an ailing European Union to its West, the sovereignty of the Ukrainian state is precarious.

Support for Ukrainian Independence in December, 1991

It’s not that Ukraine has been a thriving state since its independence. The Economist did a comparison of Poland and Ukraine since the 1990s and found that, over time, the former managed to greatly outpace the latter. In a report entitled “Slipping Away From the West”, this was their dour assessment of Ukraine’s prospects:

Over the last year or so its economy has almost collapsed. Much of the country’s industrial production, in the east of the country, has been destroyed. Nervous investors are fleeing. Its public-debt-to-GDP ratio has probably hit 100%.

Yet with Russia’s annexation of Crimea, it’s the perception of Western dominance that has taken a hit.

Russia’s power grab came amid the fallout of the 2014 Ukranian Revolution, which ousted pro-Russian President Viktor Yanukovych. Pro-Russian separatists in the South and East of Ukraine mounted an uprising against the post-revolution Ukrainian government, with the support of the Russian government and it’s military. It was purported that the annexation of Crimea was done under the authority of referendum, but as Reuters reported in March of 2015, Putin had ordered officials to start working on the reincorporation of Crimea in February of 2014.

Putin’s disregard for Ukrainian sovereignty may portend further Russian aggression in Eastern Europe, particularly in the territory once known as “Novorossiya”.

This is not the first time that Russia has intervened in the governance of a former Soviet state — according to Richard Kraemer and Maia Otarashvili:

The Russian invasion of Crimea is simply a further — though much larger scale and more dramatic — chapter in a very familiar post-Soviet saga.

If Putin were to integrate Novorossiya into the Russian Federation, Ukraine would lose almost half of its population, as well as its access to the Black Sea. Given that Putin has guaranteed the protection of Russians abroad, it is not improbable that Russia will respond to pro-Russian protests in the South and East of Ukraine with a takeover. Stratfor has simulated six possible offensive operations that Russia could direct in Ukraine.

To complicate matters further, the United States has just elected Donald Trump, who has repeatedly questioned the value of the U.S.’ NATO commitment, and commonly construes European allies as a burden.

Adrian A. Basora and Aleksandr Fisher, who in a piece written two years ago assert that Russia is set on retaking Novorossiya, suggest leaders in “Ukraine have become convinced that the fate of their independence rests in the hands of the West.”

Trump, who has been popularly criticized for his warm regard for Putin, dubbed Putin’s annexation of Crimea as “so smart” in an interview with Fox News (listen at 7:02), and questioned the U.S.’ involvement in the matter in a speech to the National Press Club in 2014.

His presidency is likely to further embolden — more so than under the Obama administration — Putin in his ambition to weaken the West, and assert his influence over former Soviet states. If Trump stays true to his isolationist posturing, it will fall to the European Union to defend the fledgling democracies of Eastern Europe and the liberal world order that has been maintained by the Western allies since the end of World War II.

European policy makers and observers have been increasingly advocating for a European security force, a military capability more robust than the current European Defense Agency. Dalibor Rohac of the American Enterprise Institute contends, “The very survival of Central and Eastern countries is at risk in a world bereft of a vigilant American presence,” and recommends a more cohesive European foreign policy and military approach.

Federica Mogherini, the high representative of the EU, has committed to protecting Eastern European countries, stating, “We have the responsibility to play the role of an ‘indispensable power’ for peace and security in our region and the world.”

The EU entered into an economic association agreement with Ukraine in 2014, and in 2016 Ukraine joined the Deep and Comprehensive Free Trade Agreement. President Poroshenko aims to apply for European Union membership in 2020.

In the face of Russian belligerence, the EU must band together to protect fragile democracies in Eastern Europe. Officials in Brussels, as well as the leaders in member states, must continue to advance human rights and democratic norms in the post-Soviet world.

This responsibility requires the EU to build on European military cooperation and press representatives in the United States to sustain their leadership role in the current world order. As Adrian A. Basora and Ambassador Aleksandr Fisher explain, “Putin will not be deterred by anything short of a commensurate show of resolve by the Western powers.” In order to preserve liberal democracy, the Western alliance has to show Putin and Russia that it has not grown weary and will continue to defend national sovereignty, free society, and open markets.