The Agency is as uncertain about Volodymyr Zelensky’s thinking and intentions as it is about Vladimir Putin’s. And as the Russian leader faces his biggest challenge in the aftermath of a failed mutiny, the Agency is straining to understand what the two sides will do—because President Joe Biden has determined that the United States (and Kyiv) will not undertake any actions that might threaten Russia itself or the survival of the Russian state, lest Putin escalate the conflict and engulf all of Europe in a new World War. In exchange, it expects that the Kremlin won’t escalate the war beyond Ukraine or resort to the use of nuclear weapons.
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“There is a clandestine war, with clandestine rules, underlying all of what is going on in Ukraine,” says a Biden administration senior intelligence official who also spoke with Newsweek. The official, who is directly involved in Ukraine policy planning, requested anonymity to discuss highly classified matters. The official (and numerous other national security officials who spoke to Newsweek) say that Washington and Moscow have decades of experience crafting these clandestine rules, necessitating that the CIA play an outsize role: as primary spy, as negotiator, as supplier of intelligence, as logistician, as wrangler of a network of sensitive NATO relations and perhaps most important of all, as the agency trying to ensure the war does not further spin out of control.
“Don’t underestimate the Biden administration’s priority to keep Americans out of harm’s way and reassure Russia that it doesn’t need to escalate,” the senior intelligence officer says. “Is the CIA on the ground inside Ukraine?” he asks rhetorically. “Yes, but it’s also not nefarious.”
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Neither the CIA nor the White House would give specific responses for confirmation, but they asked that Newsweek not reveal the specific locations of CIA operations inside Ukraine or Poland, that it not name other countries involved in the clandestine CIA efforts and that it not name the air service that is supporting the clandestine U.S. logistics effort.
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Intelligence experts say this war is unique in that the United States is aligned with Ukraine, yet the two countries are not allies. And though the United States is helping Ukraine against Russia, it is not formally at war with that country. Thus, much of what Washington does to aid Ukraine is kept secret – and much of what is normally in the realm of the U.S. military is being carried out by the Agency.
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“The view advanced by many that the CIA is central to the fighting — say, for instance, in killing Russian generals on the battlefield or in important strikes outside Ukraine, such as the sinking of the Moskva flagship – doesn’t play well in Kyiv,” says one retired senior military intelligence official granted anonymity to speak with Newsweek. “If we want Kyiv to listen to us, we need to remind ourselves that the Ukrainians are winning the war, not us.”
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“There are clandestine rules of the road,” says the senior defense intelligence official, “even if they are not codified on paper, particularly when one isn’t engaged in a war of annihilation.” This includes staying within day-to-day boundaries of spying, not crossing certain borders and not attacking each other’s leadership or diplomats. “Generally the Russians have respected these global red lines, even if those lines are invisible,” the official says.
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“The CIA has been operating inside Ukraine, under strict rules, and with a cap on how many personnel can be in country at any one time,” says another senior military intelligence official.
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Newsweek was unable to establish the exact number of CIA personnel in Ukraine, but sources suggest it is less than 100 at any one time.
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Now, more than a year after the invasion, the United States sustains two massive networks, one public and the other clandestine. Ships deliver goods to ports in Belgium, the Netherlands, Germany and Poland, and those supplies are moved by truck, train and air to Ukraine. Clandestinely though, a fleet of commercial aircraft (the “grey fleet”) crisscrosses Central and Eastern Europe, moving arms and supporting CIA operations.
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Russian intelligence is very active in Ukraine, intelligence experts say, and almost anything the U.S. shares with Ukraine is assumed to also make it to Russian intelligence. Other Eastern European countries are equally riddled with Russian spies and sympathizers, particularly the frontline countries.
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As billions of dollars worth of arms started flowing through Eastern Europe, another issue that the CIA is working on is the task of fighting corruption, which turned out to be a major problem. This involves not only accounting for where weapons are going but also quashing the pilfering and kickbacks involved in the movement of so much materiel to Ukraine.
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From Poland, CIA case officers are able to connect with their many agents, including Ukrainian and Russian spies. CIA ground branch personnel of the Special Activities Center handle security and interact with their Ukrainian partners and the special operations forces of 20 nations, almost all of whom also operate from Polish bases. CIA cyber operators work closely with their Polish partners.
In 1940, the German high command sent a panzer expert, Major General Wilhelm von Thoma, to North Africa to find out whether German forces should help the Italians, Bevin Alexander explains (in How Hitler Could Have Won World War II) — and also, unofficially, to look over the Italian army in action (or rather inaction): 
