Chemtrails = conspiracy?

Link: http://snardfarker.ning.com/video/killer-chemtrails-the-shocking

This is a quote from an article posted at 12160.org December 6 2009:

'CONTRAILS vs CHEMTRAILS
It is important to distinguish between contrails and chemtrails. Contrails are streaks of condensed water vapor created in the air by jet airplanes at high altitudes. Contrails can exist in two forms: water droplet and ice crystal. Contrails typically become visible about a wingspans distance behind an aircraft flying at high altitude. The trail dissipates quite quickly, usually within a minute or so. Chemtrails, on the other hand, are visible directly behind an aircraft, with little or no gap between the aircraft and the start of the trail. Chemtrails are said to vary from contrails in their length of persistence. Chemtrails do not dissipate quickly; they tend to form into mushy clouds which can block sunlight.'

And:
'There are currently three main hypothesis for the purpose of chemical spraying in the skies: weather modification, population control, and testing of biological agents on the general poplace.'