Assessment of the conditional prediction
Sacks argued that if the U.S. did not make an unambiguous, credible security commitment to defend Taiwan, China would "seize on" that hesitation and become more aggressive toward Taiwan (coercion, blockade-style pressure, etc.).

1. U.S. commitment remained deliberately ambiguous, not a clear red line.

   • The U.S. has still not created a formal mutual-defense treaty or explicit, legally binding pledge to defend Taiwan; its formal policy remains one of strategic ambiguity under the Taiwan Relations Act and the One China policy.(cnbc.com)
   • President Biden has several times verbally said the U.S. would defend Taiwan militarily, but each time the White House quickly clarified that official policy had not changed, preserving ambiguity rather than establishing a clear "red line."(cnbc.com)
     This matches Sacks’s condition: Washington did not move to a fully unambiguous, credible defense guarantee.

2. China has markedly escalated coercive and military pressure on Taiwan.
   Since the podcast in July 2020, China has:

   • Increased PLA air incursions into Taiwan’s ADIZ from hundreds per year in 2020 to well over a thousand annually by 2022–23 and new record levels in 2024–25, with frequent crossings of the Taiwan Strait median line.(theguardian.com)
   • Conducted large-scale live‑fire and encirclement drills around Taiwan after 2022 (e.g., following Nancy Pelosi’s visit), widely described as rehearsals for blockade or invasion operations.(cnbc.com)
   • Intensified gray‑zone tactics—near‑daily air and naval activity, cyber attacks, disinformation campaigns, and physical interference with undersea cables—explicitly aimed at coercing and exhausting Taiwan without open war.(lemonde.fr)
     These are precisely the kinds of coercive and quasi‑blockade behaviors Sacks warned about, even though full-scale annexation or a formal blockade has not occurred.

3. China has explicitly “seized on” narratives of U.S. weakness/unreliability.
   Chinese state media and officials have repeatedly used episodes like the U.S. withdrawal from Afghanistan to argue that the U.S. is a weak, unreliable partner that would abandon Taiwan, pairing this messaging with nearby PLA drills.(cnbc.com) Analysts describe this as Beijing exploiting perceived U.S. hesitation and decline to pressure Taiwan and test U.S. resolve—exactly the mechanism Sacks described.

4. Why this is scored as “right” rather than “ambiguous.”

   • The condition of the prediction (continued lack of an unambiguous U.S. defense guarantee) clearly holds.(cnbc.com)
   • The consequence—China “seizing on that” through more aggressive actions short of invasion (coercion, encirclement drills, record incursions, and psychological operations questioning U.S. resolve)—has plainly occurred and intensified since 2020.(fpri.org)
   • While we cannot mathematically prove causality, open-source evidence shows Beijing explicitly linking U.S. perceived weakness/unreliability to its messaging and drills around Taiwan, which is strong qualitative support for Sacks’s claim.

Because both the antecedent (no clear U.S. red line) and the predicted reaction (China exploiting that by ramping up coercive and military pressure on Taiwan) are borne out by events from 2020–2025, this prediction is best evaluated as “right.”