The core historical assertion — that the USS Spruance became the first U.S. Navy ship in almost 40 years to fire its deck gun at another vessel — is fully confirmed by multiple independent, authoritative sources. A named U.S. Navy official placed the prior instance at April 18, 1988, during Operation Praying Mantis, making the 38-year interval consistent with 'almost 40 years.' The CENTCOM press release, Pentagon video, Military Times, CNN, The War Zone, and Naval News all independently corroborate the April 19, 2026, engagement. Two identifiable inaccuracies prevent a TRUE verdict. First, the ship name 'USS Sprawns' is incorrect; the vessel is the USS Spruance (DDG-111) — a factual error in a named proper noun, most plausibly a phonetic mispronunciation on air or a transcription artifact, but an error of fact nonetheless. Second, the target is characterized as 'an enemy boat,' when the Touska is a large (294-meter), Iranian-flagged civilian cargo ship under U.S. Treasury sanctions — not a military boat or small craft; every authoritative source explicitly identifies it as a civilian cargo vessel. Per the MOSTLY_TRUE boundary test, the core directional assertion (historic first use of deck gun in ~38 years) remains substantially correct after correcting both errors, and neither inaccuracy reverses the primary claim's meaning. The ship-name error is likely a mispronunciation of a genuine ship, not a fabricated vessel; the 'enemy boat' characterization overstates the adversarial military character of the target but does not undermine the historical milestone framing. MOSTLY_TRUE is the appropriate nomination (per the TRUE/MOSTLY_TRUE boundary: the core assertion is substantially correct with identifiable inaccuracies that do not reverse its directional meaning).