MOSCOW — First U.S. and Russian diplomats faced off in Geneva. Then NATO received a Russian delegation in Brussels. Finally, the Organization for Security and Cooperation in Europe will sponsor talks in Vienna Thursday.

Russia courted all this attention by massing some 100,000 troops near its border with Ukraine, raising fears of a Russian invasion. Analysts read Russia's buildup as an attempt to pressure the U.S. and its European allies into concessions on a series of far-reaching "security guarantees" sought by Moscow.

What does Russia want and why is it so hard for the U.S. to meet Moscow partway? Here's a guide.

1. Russia wants a guarantee Ukraine can never join NATO

Russia's main demand is a commitment from NATO to end its further expansion into former Soviet republics — especially Ukraine. Russia wants NATO to rescind a 2008 promise that Ukraine could someday join the defense alliance. Many observers see it as a distant prospect that Ukraine could join NATO because it doesn't meet membership requirements. But Moscow doesn't see it that way. "We don't trust the other side," Russia's chief negotiator, Deputy Foreign Minister Sergei Ryabkov, said after bilateral talks with the U.S. finished Monday. "We need ironclad, waterproof, bulletproof, legally binding guarantees. Not assurances. Not safeguards. Guarantees. With all the words — 'shall, must' — everything that should be put in."

Russia's reasoning: President Vladimir Putin views Ukraine as an extension of what he calls "historical Russia" — a part of the Russian Empire and Soviet Union, and within Moscow's "sphere of influence" today. The threat of Ukraine's westward turn after a street revolution ousted the country's pro-Russian president in 2014 was the driving force behind Russia's annexation of Crimea later that year. Ukraine's desire to join the Western alliance also led to Russia's sponsorship of separatists in the country's eastern Donbas region — in effect sabotaging its path to membership by fueling a civil war.

NATO's counter: The U.S. argues that countries have a right to choose their own alliances and NATO has a long-standing "open door policy" for potential membership. "NATO has never expanded through force or coercion or subversion. It is countries' sovereign choice to choose to come to NATO and say they want to join," Deputy Secretary of State Wendy Sherman said Wednesday after a meeting between Russian and NATO officials in Brussels. Russia's actions are making the idea of NATO membership more appealing to Ukrainians, according to opinion polls. It is unlikely, however, that Ukraine will meet the requirements anytime soon.

NATO Secretary-General Jens Stoltenberg (center) and Russia's Deputy Foreign Minister Alexander Grushko arrive for the NATO-Russia Council at NATO headquarters, in Brussels, Wednesday. Senior NATO and Russian officials met to try to bridge differences over the future of Ukraine.

Caption

NATO Secretary-General Jens Stoltenberg (center) and Russia's Deputy Foreign Minister Alexander Grushko arrive for the NATO-Russia Council at NATO headquarters, in Brussels, Wednesday. Senior NATO and Russian officials met to try to bridge differences over the future of Ukraine. / Pool photo via AP

2. Russia wants NATO arms out of Eastern Europe

The draft proposals on security that Russia sent to Western powers in December would ban NATO from deploying its weapons and forces in countries in Central and Eastern Europe that joined the alliance after 1997. In effect, that would downgrade membership for Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Hungary, Romania, Slovenia, Croatia, Montenegro, Albania, North Macedonia and Bulgaria to symbolic status at best.

Russia's reasoning: Moscow sees NATO's addition of former communist countries in Eastern and Central Europe beginning in 1997 as violating a core promise by the United States when the Soviet ARMY peacefully withdrew from Eastern Europe after the fall of the Berlin Wall. In Putin's view, the West took advantage of Russian weakness in expanding the alliance over multiple Russian objections. "And where is it written down on paper?" recalled Putin in recounting NATO's decisions to expand eastward in subsequent years. "They would say to us. 'It's not on paper? Well then get lost along with your concerns.' And that's the way it's been year after year." Now Putin appears to be acting as if Russia is in a position to dictate new terms — and rewrite the story of the end of the Cold War.

NATO's counter: U.S. officials have made clear they believe even Russia knows this demand is unrealistic. Acceding to Russia's proposal would mean redrawing the map of Europe after the Cold War and placing Moscow's security demands above the concerns of whole swaths of Europe that were once under Russian Soviet control. Western officials also contest the idea the alliance promised not to expand and say it was Russian actions that led NATO to beef up deployments in the new member states. "NATO never even had any forces on its eastern edge because we didn't feel the need to have troops close to Russia until Russia invaded Ukraine in 2014 and led NATO members to be concerned that they might keep going into NATO territory," Victoria Nuland, undersecretary of state for political affairs, said Tuesday.

This photo taken from video distributed by Russian Defense Ministry Press Service shows Russian military vehicles move during drills in Crimea, April 22, 2021.

Caption

This photo taken from video distributed by Russian Defense Ministry Press Service shows Russian military vehicles move during drills in Crimea, April 22, 2021. / Russian Defense Ministry Press Service via AP

3. Russia wants a ban on NATO missiles within striking distance

Russia says it wants a ban on intermediate-range missiles in Europe — in effect, reinstating a Cold War-era treaty abandoned in 2019 by the Trump administration, which accused Russia of repeated violations. Believing that the Biden administration is game for a deal, the Kremlin says it wants to bundle arms control progress with its other grievances against NATO expansion. "Are we putting our rockets near the borders of the United States? No we're not," argued Putin to a Western journalist during a press conference in December. "It's the U.S. with its rockets coming to our doorstep."

Russia's reasoning: While Ukraine could be a long way from NATO membership today, Russia has nervously watched as NATO has demonstrated it can deepen its involvement in Ukraine — providing weapons and training — without the former Soviet republic becoming a member. Russia's president has made no secret he envisions a day in the not-so-distant future when NATO missiles could be housed on Ukrainian soil within minutes' striking distance from Moscow. "For us this is a serious challenge — a challenge to our security," Putin said.

NATO's counter: This could be an area of compromise. For starters, some Democratic lawmakers opposed the Trump administration's decision to abandon the Intermediate-Range Nuclear Forces Treaty with Russia.

4. Russia wants autonomy for eastern Ukraine

Russia says Ukraine must meet its obligations under 2015 agreements to end THE fighting between Ukraine's army and pro-Russian separatists in eastern Ukraine that has killed some 15,000 people. That peace deal, known as the Minsk agreements, has stalled and Ukrainians are killed practically every week, but it allowed Russia to largely keep up the fiction it is not a party to the war in the Donbas region. Moreover, the Minsk agreements would provide additional autonomy to the separatist Russian-speaking territories in the Donbas.

Russia's reasoning: Moscow has long believed the U.S. calls the shots in Kyiv and the U.S. has expressed support for the Minsk accords as a path toward deescalation. Moreover, for Moscow, it's a way to guarantee rights for Russian speakers in the Donbas — and provide the Kremlin leverage into Ukrainian affairs going forward.

NATO's counter: The U.S. supports the Minsk agreements. Kyiv is less enthusiastic. The deal as signed rewards Russia for stirring up the conflict — meddling that Russia denies. Kyiv and Washington argue Moscow has also failed to meet obligations to the deal.

Michele Kelemen contributed to this explainer from Washington, D.C.

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