[editor-surveyor]

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The “one second” melt is where you lost me.

But laser weaponry mostly uses capacitive discharge rather than big generators, and the target is more likely to be a missile warhead by design.
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[palmer]

Because of the energy transfer. Energy is independent of the use of capacitors. Most laser is pulsed so it can use capacitors or other energy storage to do that. The one second comes from the amount of time on target. If you spend more than one second, then you lower the energy generation that is required. For example if you spend 10 seconds melting each wheel then you only need 250 kW for the power source.

Again, it does not matter whether you charge and discharge capacitors, the energy required is the same. Capacitors do not create energy.

If your targets are warheads they do not need to be melted like an alloy wheel, just penetrated and that takes less energy (and/or time). Wikipedia says "While the ABL's laser required 55 kg (121 lb) to generate one kW, the MDA wanted to reduce that to 2–5 kg (4.4–11.0 lb) per kW, totaling 5,000 lb (2,300 kg) for a megawatt" My estimate of 100,000 pounds for 2.5 MW was a little low for ABL but a much lighter power supply is envisioned.

Please try to remember, the claim that wheels can't melt in a forest fire and therefore must have been melted by someone with a beam weapon is your claim, not mine. My one second per wheel assumption is simply a realistic assessment of the engagement with the target. It could be a little longer but not much longer.