https://www.wsj.com/articles/classified-document-leak-russia-ukraine-war-offensive-u-s-intelligence-dfda36c9?mod=opinion_lead_pos1
The leak of classified U.S. documents related to the Ukraine war looks like a debacle at many levels—undermining the confidence of allies in the U.S., revealing how much the U.S. knows about Russia’s military deliberations, and above all betraying the weakness of Ukrainian air defenses.
The source of the leak isn’t known, which is disconcerting on its own. The documents first appeared on social media, and the press hasn’t been able to verify their authenticity. But the obvious alarm among U.S. officials suggests that much of the leaked intelligence is accurate. The Justice Department and Pentagon began a criminal investigation last week, for what that is worth.
The leaks are especially damaging because they disclose secret U.S. judgments about the progress of the war. It’s not the same as betraying the location of troop movements, but it’s close. The disclosure of how much the U.S. knows about Russian military plans could be a death sentence for sources in Russia.
The most troubling leak is that Ukraine’s air defenses could be defeated by May, which would give Russia air superiority and a huge tactical advantage. The Kremlin hoped air dominance would help it achieve an early victory, but Ukrainian air defenses held up well against the initial assaults.