BBC News, Venezuela
Under the blazing midday sun, at an army base outside Caracas, middle-aged Venezuelan military commanders were being told how to teach the civilian population in guerrilla warfare.
Lt Col Antonio Benavides is training officials to instruct reservists
Hundreds of officers in olive combat dress were shown practical displays of Venezuela's new military thinking: The use of civilians to fight a war of resistance in the event of an invasion.
They are now using this knowledge to train around 2m civilians to become military reservists.
The first half-a-million adults are already being put through the four-month programme. The rest are expected follow over the coming months.
Lt Col Antonio Benavides, of the elite National Guard commando regiment, is responsible for training many of the military professionals who will in turn instruct the reservists.
Lt Col Benavides started the first lesson of the day: The art of camouflage.
"Here we have a hidden underground tunnel system like the Vietcong used in Vietnam against the American aggressors," he said, pointing to the entrance of a dark hole in the ground.
"This is the kind of tunnel that we're now teaching civilians to build."
Lt Col Benavides lined up a small group of civilian reservists to make a point about the art of surprise in guerrilla warfare.
"On the surface they look like ordinary people on the street. But if you look underneath their jackets, you will see they are hiding knifes, catapults and pistols," he told his audience.
"We're not expecting to arm all our reservists with guns. We do want them to make their own home-made weapons. Anything will do, as long as it harms the enemy," said retired Rear Admiral Luis Cabrera Aguirre, who is overseeing the training given to civilian volunteers.
It is this kind of territorial guard made up of civilians, President Hugo Chavez of Venezuela is now creating with the help of military drill, weapons training and lessons in citizenship.
President Chavez wants the territorial guard to act as a deterrent for any potential invasion of Venezuela.
Art of camouflage - the first lesson of the day
In his latest weekly TV show, President Chavez repeated his long-held belief that the US was planning to invade Venezuela, saying that Washington wanted to overthrow him.
General Juan Alberto Hernandez, of the National Guard, told the BBC that a group of Venezuelan officers had taken part in a large-scale military exercise in Cuba.
"They reported back to us that they were impressed with what they saw. Cuba's civilian population was working hand in hand with the professional army to defend the country. This is a lesson we are learning from Cuba."
The concept of a civilian militia is nothing new in Venezuela. Almost half a year ago, small neighbourhood groups of Chavez supporters began holding informal gatherings on a weekly basis. The meetings were limited to military drill.
But the idea has come a long way since. More than 2m adults have signed up to become reservists in a programme run by the armed forces and are now having to give up a Saturday each week.
'Instrument of repression'
At an office inside the headquarters of Venezuela state owned oil company, PDVSA, Alfredo Carquez reflects on his experiences as a new recruit for the territorial guard.
"At first my family wasn't too impressed that when I signed up," said Mr Carquez, a 43-year-old executive who works for the firm.
"But they have accepted it now because I explained to them that I feel obliged to defend my fatherland and any threat to the revolutionary process being carried out by President Chavez."
Venezuelans are being trained in guerrilla warfare
Mr Carquez and many others like him feel they are privileged to work for the government in relatively secure and well-paid jobs. So they feel they want to put something back into the system.
But it is not just government employees who have become trainees in the reserve. A whole cross-section of society including housewives and pensioners has come forward to serve in the territorial guard.
However, former military officers close to the opposition warn that the territorial guard could be used to quash popular dissent against President Chavez.
Retired Vice Admiral Mario Ivan Carratu Molina said: "Remember that the territorial guard is directly answerable to the president. So he could use it as an instrument of repression against a popular uprising, for example."
There is currently a debate in Venezuela's parliament whether service in the reserve should be made compulsory for all Venezuelans.
Several high-ranking military officers have told the BBC they are reluctant to force citizens into military service.
However, a group of pro-Chavez lawmakers argues that the country needs a well-trained reserve force and that making it compulsory is the only way to make that happen.