Lasers are a growing problem on battlefields as more weapons and equipment make use of them. While laser light shows, and science fiction movies, give the impression that you can see lasers, in most cases you can't. You can see them in laser light shows because the laser operators first put smoke or water vapor into the air so that the lasers will diffuse (bounce off smoke and water particles) and become more visible. Most lasers are invisible to the naked eye. This is why U.S. combat troops are often seen with goggles on their helmets. These items not only protect the eyes from dust and sand, but also from the damage most lasers will do to the eyeball. Despite the effectiveness of cheaper GPS guided bombs, laser guided bombs are still more accurate, and the frequencies of the lasers used for targeting are constantly changed so that the enemy cannot use their own lasers to "spoof" (lure the bomb away from the target). Because lasers are used as range finders for so many weapons, as well as target designation for bombs and missiles, most modern tanks come with a laser detector, which can not only alert the crew that they are being lased, but by what kind of laser and what is likely on the way (missile, bomb or tank shell.) The modern battlefield is full of laser light, and that trend is expected to continue.