Maduro in turn has granted it vast powers, not just in military matters but over key government ministries -- active or retired officers head 12 of 32 ministerial posts -- and in vital economic sectors including petroleum.
The military's capabilities -- and its loyalty under duress -- are core concerns at a time when its leaders have claimed that a "paramilitary" force led by a deserter and backed by "foreign governments" has attacked a military base in what might be seen as an incipient coup attempt.
Despite its pledge of "absolute" support to Maduro, the military is under strong pressure, blamed by the opposition for violently quelling protests and urged by it to switch sides. The loss of its backing would spell the end of Maduro.
Here are some key facts about the Venezuelan military, formally the National Bolivarian Armed Forces, or FANB.
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Armed power
The FANB has some 365,000 troops (army, navy, air force, national guard and reserve), only 1,000 fewer than Brazil, according to the Latin American Security and Defense Network, a policy and analysis center.
But Venezuela has 30 million people; Brazil has 210 million.
In 2006, the United States prohibited the sale or transfer of military arms or technology to Venezuela, whose then-president, Hugo Chavez, had closely allied the country with Russia and China.
Russia has supplied Venezuela with rifles, anti-tank rocket launchers, tanks and other combat vehicles, artillery, anti-air defense systems and combat planes, helicopters and missiles, according to the NGO Control Ciudadano, which monitors military activity.
China has provided communications gear, uniforms, radars, armored vehicles, planes and helicopters.
Political power
Of the 32 cabinet posts in the Maduro government, 12 are held by military men, 10 of them active-duty and two retired.
The military is commanded by General Vladimir Padrino, the defense minister, and by General Remigio Ceballos, commander of operational strategy. Padrino is a sort of "superminister," to whom other cabinet members must report, Maduro said last year.
Among the key cabinet posts in military hands are the interior and justice ministries; the food ministry; agriculture and lands; and energy.
The opposition blames Food Minister Rodolfo Marco Torres, a retired colonel, for the severe shortages plaguing the country.
Opposition leaders have sharply criticized what they call the "politicization" of the military under Maduro and his predecessor. "The worst error committed by Chavez was to bring the military out of the barracks" and into the streets, said Henry Ramos Allup, a former National Assembly president.
"Who is going to put them back?"
Economic power
A television channel, a bank, an auto-assembly plant and a construction group -- these are some of the businesses controlled by the Venezuelan military, joining the Military Mining, Gas and Petroleum Company known as Camimpeg.
The latter performs functions similar to Petroleos de Venezuela, or PDVSA. the state-owned petroleum company. It repairs and maintains oil wells, and sells and distributes the products of the oil, gas, mining and petrochemical industries.
Camimpeg is at the heart of the "military-industrial engine," a Maduro idea for confronting what he sees as the "economic war" being waged by the opposition and sympathetic businesses to destabilize his government.
