But for a policy that’s purportedly a pillar of the decades-old international order, military aid to Ukraine is pretty new. The U.S. government has provided more than $1.6 billion in security assistance to Ukraine since 2014, when Russia intervened militarily in eastern Ukraine and illegally annexed the Ukrainian territory of Crimea following an uprising that overthrew the country’s pro-Moscow president.

Barack Obama suggested that defending Ukraine against Russia wasn’t a core U.S. national-security concern—and that even if the United States did have interests in Ukraine, Russia had more, meaning that Moscow would always be willing to do more than Washington to keep Ukraine within its sphere of influence. As Obama told The Atlantic’s editor in chief, Jeffrey Goldberg, at the end of his presidency, “The fact is that Ukraine, which is a non-NATO country, is going to be vulnerable to military domination by Russia no matter what we do.”

Read: We now know just how confusing Trump’s Ukraine policy was

That point of view has decidedly shifted. When the Trump administration inexplicably held up security assistance from mid-July to mid-September of 2019, a bipartisan uproar in Congress compelled the White House to reinstate it.

What’s attracted the most attention about the aid package is that Trump broke with Obama’s policy and in 2018 began sending lethal weaponry such as Javelin anti-tank missiles and launchers to the Ukrainian military, a matter he and Ukrainian President Volodymyr Zelensky discussed in their now-infamous July phone call. But a U.S. condition of these sales was that the Javelins couldn’t actually be used in the fight with Russia and had to be stored away from the battlefield, which means they’ve effectively had only a symbolic deterrent effect. (The head of U.S. European Command says Javelin systems warehoused in western Ukraine have given Ukrainian soldiers in the east of the country “a bounce in [their] step,” for what it’s worth, which in the case of Javelins can be hundreds of thousands of dollars a pop.)

The more meaningful components of the package are U.S. military training and equipment such as sniper rifles, rocket-propelled grenade launchers, counter-artillery radar systems, night-vision technology, and various forms of medical support. That $400-million figure we keep hearing about included items like these and refers to a tranche of $250 million managed by the Defense Department and another of just over $140 million managed by the State Department.

When the conflict with Russian forces and pro-Russian Ukrainian separatists first erupted, the Ukrainian military had only about 6,000 combat-ready troops, even though its declared military manpower was well over 100,000, Mariya Omelicheva, a professor at the Pentagon-funded National Defense University, told me. Soldiers received no training at the brigade or regimental level, lacked rifles and ammunition, and had to depend largely on “battalions of volunteers funded by oligarchs” to wage the war.