Laser evaporation for orbital debris removal?

[More Boosters]

You need to think about the orbital mechanics at play here the debris is in orbit around earth fire at it from the earth surface, and the resulting ablative thrust will effectively be directed towards earth - however, this thrust will result in a radial / antiradial type of orbital manoeuver, the whole orbit will 'rotate' around the spacecraft. At one point, the orbit would intersect with the planet - ok the apoapsis will be farther from earth - but at the same time, if the periapsis has become low enough to go through the atmosphere, when the debris enter the atmo it will start to slow down (if it only pass through the high layers of atmosphere at first) and will end up being delrbited due to drag and will burn during atmospheric reentry.)

edit : here's what doing radial/antiradial manoeuver looks like in KSP (i only tugged at the blue manoeuver node outwards)

i have precise node and KER opened so you can check the orbital parameters (ok, 'besides, it works in KSP' is a corny line, but in this case, it would do the same in real life )

http://i.imgur.com/0HyWB7Hl.png

So you want to radially boost one side of the orbit enough so that the other half of the orbit crosses the atmosphere, okay that makes sense.