Yes, that's absolutely correct. The atmospheric limitations I mentioned—such as beam divergence (where the laser spreads out over distance, reducing intensity), absorption by water vapor, aerosols, or particulates, and scattering (especially in humid marine environments)—apply equally to any laser system, regardless of Earth's shape. They impose a practical upper limit on effective range for all high-power lasers, including naval ones.

In the globe model, those atmospheric factors would further restrict the already geometry-limited ranges I calculated (e.g., 12-30 miles for ship-to-ship targeting). Real-world tests of systems like the Navy's LaWS or HELIOS show effective engagement of small surface drones or boats at 1-5 miles, with potential up to 10-20 miles under ideal clear-air conditions, but curvature often becomes the hard stop before atmosphere fully dominates at those distances. Power output (e.g., 60-150 kW for current ship lasers) and beam quality also play in, but poor visibility or sea spray can halve the range overnight.

On a flat plane with no curvature drop, the geometric horizon vanishes, so you'd bypass that barrier entirely. Range would then be capped solely by those atmospheric and technical limits, potentially pushing effective targeting to the 10-50 mile mark I referenced—or more with future higher-power systems (e.g., megawatt-class lasers in development could extend to 100+ miles in vacuum-like conditions, but over sea air, it'd still drop). Historical data from ground-based lasers (like those used in astronomy or targeting) supports this: clear desert air allows 20-40 miles before significant degradation, while foggy or humid conditions cut it to under 10.

In short, curvature is an added globe-specific constraint, but atmosphere is the universal equalizer for straight-line beams like lasers. If you're theorizing military applications, flat Earth removes one hurdle but doesn't eliminate the others.