Aiming a laser pointer at an aircraft is a felony in the US. The seemingly small light can reach all the way to the cockpit of a plane flying up to 12,000 feet, where it becomes magnified by the Plexiglass windows, creates a strobe effect, and compromises the pilot’s vision. Source Source 2 Source 3

The FBI arranged for a video to demonstrate what a consumer-grade laser pointer looks like to a pilot: