jcc: To interact with some atoms, the laser light must be at a frequency at which it will be absorbed by the atoms. A suitably-tuned laser will interact with smoke particles or a flame. Where did you read that "the strongest laser beam cannot bend flame or move smoke"? Or is this based on your own experience in some way? Laser light can be affected by electromagnetic fields - particularly its polarisation. An electric field or a magnetic field alone will not bend a laser beam because, as paddoboy said, the laser beam does not contain any charged particles. A laser that melts steel is absorbed by the steel. The same light will not necessary be absorbed by a diffuse gas such as in smoke or a flame. Electromagnetic waves have no charge either. Photons are essentially electromagnetic waves (in quantised packets). In the photoelectric effect, an incoming photon must have a frequency suitable to lift an electron out of one of the occupied energy levels of the metal that it is falling on. If the photon frequency is too low, nothing happens. When a photon ejects an electron, the photon is absorbed by the electron and its energy goes partly to removing the electron from the metal, with any excess ending up as kinetic energy of the ejected electron. It is not the impact of the photons that cuts the steel. It is the depositing of the energy of many photons in the metal, causing it to heat and eventually melt. Yes, but only if the photon frequency is just right so that the flame atoms can absorb the light. This effect is the principle by which laser cooling of diffuse atoms works, by the way. Bose-Einstein condensation relies on exactly the effect of absorption of photons by a diffuse gas that you are describing. Hope this helps!