A Ukrainian 3rd corps ran a multi-brigade offensive and, by its commander's count, lost seven times fewer soldiers than Russia, most of them wounded. 250 prisoners — company commanders among them, most likely a battalion commander. 12,000 captured drones. Hundreds of armoured vehicles left where they stood. Asked when it happened, the man advising that corps answers: "I can't talk about the timeline at all" — because the weaknesses Third Corps exploited are still open. This is Operation Vivaldi, the campaign in the Lyman direction that broke Russia's plan for the year.

Our guest goes by the call sign Jackie. American, a self-described "forever sergeant," he is the senior American military advisor to Ukraine's Third Army Corps. He came to Ukraine in 2022, was wounded almost immediately, and spent his first weeks in a Ukrainian hospital working out who he was fighting for. Rob Lee joins as co-host, so you get the operational picture and the man inside it at the same time.

Along the way: the avalanche assault, ground drones appearing behind Russian lines, a remote-driven BTR-60 packed with ammunition, the mid-strike campaign and the cappuccino line — the last place you can get a barista-made cappuccino before the battle area; Ukraine's sits 23 kilometers back, Russia's is nearing 50. Why every infantryman is now a SIGINT specialist. How a unit that cannot legally punish anyone enforces discipline with trust, honesty and the after-action review. And the story of Grady Kurpasi, the Marine who should have been commanding part of the fight he died in as a rifleman.

Recorded in Kyiv.

Key moments:

0:00 - Maneuver is dead: the verdict Vivaldi broke

13:01 - "I can't talk about the timeline at all"

24:51 - What Vivaldi was for: defeat the northern pincer

40:50 - The avalanche assault, explained

47:40 - Ground drones behind Russian lines

55:04 - The mid-strike campaign: pulling the Russian line back

86:23 - The BTR-60 turned remote-driven bomb

92:26 - Third Corps history: 2014 and the men who knew the enemy

108:16 - The cappuccino line: the most honest metric of this war

113:22 - Culture beats technology: the mind is the weapon

137:37 - The training pipeline: 51, 24, and 14 days

154:43 - The AAR as the only discipline that works

163:11 - Grady Kurpasi: the story to stay for

Produced by the Borderlands Foundation.

Support our work: https://theborderlandsfoundation.org

Why War Matters — Sam's new Washington, DC talk for founders:

https://ukraineforfounders.com/talk/

All episodes: https://ukrainemilitaryhistory.org/

Guests:

Rob Lee: https://x.com/RALee85

Third Army Corps: https://ab3.army

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