A friend and I have been going back and fourth about whether a laser could effectively go through people, given that 70% of the body is water. He is of the opinion that the high water content would create a situation where there is a smoldering mess, but no clean cutting action. I am of the opinion that a focused, high-power beam should be able to vaporize living tissue quite easily, especially considering we have 40kw lasers already and 100kw models are around the corner. I would appreciate some referenced debate on the issue if possible, but anecdotal experience could be useful (because there aren't many double blind studies involving the power levels needed to vaporize living beings, for obvious reasons)

The question stems from the planned deployment of the Advanced Tactical Laser by the U.S. Military. Since both my friend and I are veterans and work in the defense industry, practicality of systems such as this come up a lot.

We are in the business of the unpleasant, so we are wondering what happens if, perhaps, this system is used on a target who is exposed in his vehicle. We assume he's surely know something is up, but we want to know if a megawatt-class laser would produce 3rd degree burns, or instant casualties.

This is a very real concern, about planned military activities. It should be address specifically because it's "unpleasant" to most people. It is in the same vein that discussion caused the outlawing of flamethrowers and land mines.