We must not succumb to the image of the "Star Trek" type phaser beam....they all disperse with the square of the distance away. As the knowledgeable poster on Page one said....the best lasers shot at the moon are 5 times the moon's diameter when they arrive there.
Not that it matters - but the best lasers could make a spot on the moon about 2 km in diameter.
see this blog
This
is the internet! Beware "knowlegeable" [sic] posters!