Hmmm... Chem Trails? Or were they insects? What is your theory?

One of the cheapest and most destructive weapons available to terrorists today is also one of the most widely ignored: insects. These biological warfare agents are easy to sneak across borders, reproduce quickly, spread disease, and devastate crops in an indefatigable march. Our stores of grain could be ravaged by the khapra beetle, cotton and soybean fields decimated by the Egyptian cottonworm, citrus and cotton crops stripped by the false codling moth, and vegetable fields pummeled by the cabbage moth. The costs could easily escalate into the billions of dollars, and the resulting disruption of our food supply – and our sense of well-being – could be devastating. Yet the government focuses on shoe bombs and anthrax while virtually ignoring insect insurgents.
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Seeing the potential, military strategists have been keen to conscript insects during war. In World War II, the French and Germans pursued the mass production and dispersion of Colorado potato beetles to destroy enemy food supplies. The Japanese military, meanwhile, sprayed disease-carrying fleas from low-flying airplanes and dropped bombs packed with flies and a slurry of cholera bacteria. The Japanese killed at least 440,000 Chinese using plague-infected fleas and cholera-coated flies, according to a 2002 international symposium of historians.

During the Cold War, the US military planned a facility to produce 100 million yellow-fever-infected mosquitoes a month, produced an “Entomological Warfare Target Analysis” of vulnerable sites in the Soviet Union and among its allies, and tested the dispersal and biting capacity of (uninfected) mosquitoes by secretly dropping the insects over American cities.