Evidence shows a major escalation, but not clearly the kind of regional war Sacks seemed to be talking about, and his claim was probabilistic (≥50%), not categorical.

Key facts:

• Since October 2023, the Middle East has been in a multi‑theater “Middle Eastern crisis” involving Gaza, Lebanon/Hezbollah, Syria, Yemen/Houthis, Iraq‑based militias, and Iran–Israel tensions, with U.S. and U.K. military involvement and attacks across several countries.(en.wikipedia.org)
• In June 2025 there was a direct Iran–Israel war (“Twelve‑Day War”) with large Israeli strikes on Iranian nuclear and military sites, massive Iranian missile and drone barrages on Israel, and U.S. airstrikes on Iranian nuclear facilities, plus an Iranian missile attack on a U.S. base in Qatar.(en.wikipedia.org)
• Analyses of that conflict emphasize that, despite its intensity and the wider regional crisis, it “did not escalate into a broader regional war but remained geographically and operationally limited,” with Hezbollah, the Houthis, and others acting in constrained ways rather than triggering a full multi‑state regional war.(diplomatmagazine.eu)

Interpretation issues:

• Whether this amounts to the “regional war” Sacks feared is partly definitional: some might argue that simultaneous fighting involving Israel, Iran, U.S. forces, and Iran‑aligned groups across multiple countries is already de facto regional; others, including the cited analysts, explicitly say it stopped short of a broader regional war.
• His prediction was that the odds were “at least 50–50” that tensions would escalate to such a regional war in the “foreseeable future.” Because this is a probability estimate with a vague time horizon and an imprecise event definition, observing one world in which the conflict escalated heavily but was still widely described as not a full regional war does not let us cleanly judge the forecast as simply right or wrong.

Given the mixture of (1) substantial escalation including an Iran–Israel war, (2) credible expert characterizations that it did not become a true broader regional war, and (3) the inherently probabilistic, time‑fuzzy nature of the prediction, the outcome is best classified as ambiguous rather than clearly right or wrong.