On several consecutive mornings in early 2014, I woke up with one agonizing plea: Please, Lord, let the Ukrainian service members still be alive. I feared that while I slept, Russians might have slaughtered thousands of outgunned and outnumbered Ukrainians trapped on their own air and naval bases.

Hostilities between Russia and Ukraine began in that year with Russia’s lightning-quick occupation of Crimea, a region coveted by Russian President Vladimir Putin. Within hours, Ukrainian service members at various military installations were trapped on their own soil by Russian forces. If they had fought back, almost certainly they would have died. If they didn’t resist, it was unclear how they would fare. My job, as deputy assistant secretary of defense, was to lead a team drafting proposals for then-Defense Secretary Chuck Hagel and President Barack Obama, outlining options for the United States to help Ukraine defend itself against further Russian aggression.

The situation was urgent: Viktor Yanukovych, the corrupt, Russia-friendly president of Ukraine whose election was aided by Paul Manafort — Donald Trump’s future campaign chairman and, as of last year, a felon — had overseen years of government plunder. His military was under-resourced and gave up without a fight. The Russians seized dominance of the air and sea, illegally took over Crimea and started a separatist war in the Donbas region of eastern Ukraine that persists today. At the outset, Ukraine’s government sought both lethal and nonlethal aid from Western nations. The Obama administration announced a $53 million nonlethal aid package later that year.

Republicans in Congress criticized Obama for not providing weaponry. They praised President Trump after he approved arms sales to Ukraine in 2017, including the Javelin antitank systems mentioned by Ukrainian President Volodymyr Zelensky in the July 25 call with Trump that’s at the heart of the House’s impeachment inquiry. Now, though, Trump is accused of delaying nearly $400 million in military aid at around the same time he encouraged Zelensky to look for compromising information about one of Trump’s political rivals, former vice president Joe Biden, whose son Hunter Biden was on the board of directors of the Ukrainian gas company Burisma.

In the context of Ukraine’s shooting war — and the political war between the United States and Russia — Trump’s alleged actions suggest his contempt for his constitutional duty and his lack of stewardship of American military and diplomatic resources. But they’re also a reminder of his persistent flirtation with prerogatives claimed by Putin, unquestionably a U.S. adversary. Trump’s motivation may have been domestic politics, but Putin’s machinations made Ukraine vulnerable to Trump’s apparent push in the first place.

In 2016, Ukrainian officials found a ledger that catalogued payments made to Manafort by Ukraine’s government. Around the same time, Manafort was denying reports that he had played a part in weakening language in the Republican Party platform regarding assistance to Ukraine in its war against Russia.

Before and after that, Ukrainians have died fighting Russia-supported military elements that the Kremlin has denied sending. This year, three Russians and a Ukrainian were charged in the Netherlands in the 2014 downing of Malaysia Airlines Flight 17 over Ukraine with a Russian-made Buk missile, killing 298 people. Russian-backed forces have not pressed all the way to the Ukrainian capital, Kiev, mostly content to let the fighting stalemate in the east.

This has continued for five years. During that time, the United States has provided more than $1 billion in defense-related aid to Ukraine. The European Union and Western allies have given billions in loans and millions in other forms of aid. Meanwhile, the war drags on — in a report from February, the United Nations tallied more than 13,000 deaths. Ukrainians, rightly, continue to insist that Russia has no right to their territory or to determine their political fates.

We are supporting Ukraine to stop Putin. If Russia succeeds in Ukraine, Moscow will use military aggression again. Eventually, Russia could move against a NATO ally, which would almost automatically require us to go to war pursuant to NATO’s Article 5 principle and provision that “an attack against one” is “an attack against all.”

This summer, Ukrainians elected Zelensky, a 41-year-old entertainer and political newcomer, on the basis of his anti-corruption platform. Zelensky has also signaled that he wants to make peace with Russia. If anything, Trump should have been increasing support to Ukraine so as to strengthen Zelensky’s negotiating hand with Putin. Instead, as we’ve learned from Trump’s own statements, from news accounts and from the rough transcript of the July 25 call, he and his administration held up vital military assistance to Ukraine and pushed for an investigation of Biden, as well as the investigation into 2016 election.

Imagine if our president hinted to a NATO ally under attack — let’s say Britain — that he would come to its defense only if Prime Minister Boris Johnson did him a favor. Conversely, imagine if another ally’s leader, such as Israeli Prime Minister Benjamin Netanyahu, were to tell Trump that he would help us defend ourselves only if Trump helped him politically.

It’s this kind of scenario that Trump stands accused of now. If his apparent actions had remained secret, it could have kept aid from flowing to Ukraine; Ukraine’s government could have been able to blackmail our president by threatening to publicize his request. Any other country with access to this conversation, via espionage, might have been able to do so as well. Trump’s actions, then, could simultaneously amount to a betrayal of public trust, a fraudulent manipulation of allocated funds, a roadblock to U.S. policy and a counterintelligence risk. Most government employees with a security clearance would have it revoked over an episode like this. Trump, though, says his call with Zelensky was “perfect.”

Now, praise the Lord (and the brave, principled whistleblower), the secret is out. While lawmakers investigate Trump, a unified Congress and executive branch must demonstrate to Putin and the world that in the war with Russia, the United States is on Ukraine’s side. We should join European nations in pressuring Moscow to implement the Minsk Agreements, designed to protect Ukrainian sovereignty, and make clear that Ukraine isn’t a bargaining chip — either on the geopolitical chessboard or for the political gain of the American president.

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