The running theory is that if the Earth is hit by a sufficiently large meteor, that the impact would create an ice age from all the dust it would put into the atmosphere. While this has been historically seen as a bad thing, this has me wondering if people might one day want to intentionally steer a large asteroid or comet at the Earth as a way to combat global warming.

Could such an impact permanently (or simi-permanently) reverse global warming without causing so much secondary environmental damage that it would make the outcome worse than letting global warming take its course.