Policy enacted under the Clinton Administration limited the number of military trainers in Colombia to 400. As of early 2002 there were 250 American troops in Colombia, 50 Defense Department civilians and 100 contractors, some of whom operated aircraft that spray herbicide on Colombian coca fields.
In March 2002 The Bush administration drafted a plan to expand the US military role in Colombia from counterdrug training to anti-terrorism. The policy shift could require as many as 100 additional American troops to be sent to Colombia.
There is speculation of many more contractors than 100 as part of the privatization of the US military. I am posted this as a followup to the alleged plan to introduce US combat troops into Columbia in Spring 2003.