It is rare for one individual seriously to divert the course of history. To have done so virtually unnoticed was the astonishing achievement of the former Texas congressman Charlie Wilson, who has died aged 76 after suffering a cardiopulmonary arrest.His accomplishment in launching and sustaining America's largest clandestine war — supplying arms to Afghan rebels fighting the Soviets in the 1980s — might have been more understandable had he been a discreet figure sliding greyly through the corridors of power. In reality, he was a loud-voiced, 1.93m Texan, addicted to outlandish clothes and notorious for his womanising. He staffed his congressional office with beautiful female assistants (dubbed Charlie's Angels on Capitol Hill) and had well-publicised brushes with the law, including allegations of cocaine use and drunk-driving.

Yet he somehow managed to persuade the Bible belt of rural east Texas to return him for 11 successive congressional terms and to attract huge financial support from American Jews and the strict Muslims of Saudi Arabia. His inexhaustible capacity to be all things to all men brought him enormous influence in American governance, allowing him to spend the Reagan years virtually running his own foreign policy.

The key to his clout lay in the constitution's decree that the House of Representatives alone holds the power to raise and deploy federal funds. For all the document's network of checks and balances, neither president nor senate can spend a cent until the house supplies the funds.

Conversely, it is within the house's power to mandate funds for schemes that may be anathema to other branches of government. Whether a new swimming pool for a congressman's district or, in Wilson's case, a full-blown clandestine war, it is hard to block a representative determined to thrust his hands into this cavernous pork barrel.

Born in Trinity, Texas, he graduated from Trinity high school and, although enrolled at Sam Houston State University in Huntsville, Texas, Wilson had reluctantly attended the US naval academy at Annapolis, graduating in 1956. He went on to serve as a gunnery officer on a destroyer, patrolling the eastern Mediterranean. He soon became famous, through practice sessions, for running out of ammunition long before the end of each voyage. His service turned him into a first-class gunner and a ferocious anti-communist, a stance that soon led him into politics.

His first campaign, in 1961, took him into the Texas state legislature, a notoriously eccentric institution in which he cut his legislative teeth. During a 12-year stint, he showed a broadly liberal stance on social issues, supporting a minimum wage, medical care for the elderly and equal rights for women. In international affairs, however, he backed the extreme Christian right. In 1973 he ran for congress and won, despite an opposition poster showing him obviously drunk.

He had barely settled in Washington when the Yom Kippur war erupted. Having been assigned to the house foreign affairs committee, Wilson asked for a briefing from the Israeli embassy. The ambassador immediately arranged for him go to the frontline, an experience that turned him into one of Israel's strongest congressional supporters. His stance drew immediate and substantial financial support from Jews in Houston, Dallas and other parts of the country.

His travelling companion to the war zone had been another Democratic representative, Ed Koch (later mayor of New York), who used his powerful party connections to get Wilson assigned to the appropriations committee (with authority, among other things, over America's huge foreign aid to Israel). The gate to power had slid open.

This powerful committee has 50 members who control the entire federal budget. They are divided into 12 subcommittees, and Wilson was soon assigned to the one responsible for foreign operations, endowing him with enormous influence over the state department. By 1980 he had also found his way on to the defence appropriations subcommittee, which added the Pentagon and the CIA to his expanding sphere of influence.

As he later told his biographer, George Crile “Once I got on defence, I went from being the skunk to being the prettiest girl at the party.” Every member of Congress yearns for a slice of the country's annual military bill. The committee member who helps distribute this largesse generates a mountainous pile of favours awaiting return.

Wilson increased his profile when an FBI bribery sting caught a number of Democratic colleagues. Speaker Tip O'Neill, the party leader in the house, engineered Wilson's improbable assignment to the house ethics committee as it considered the future of one key party member, representative John Murtha. Loudly denouncing the proceedings as a partisan witch-hunt, Wilson persuaded fellow committee members to let the whole matter drop. Murtha, later chairman of the defence subcommittee, and O'Neill remained deeply in Wilson's debt and eventually repaid with interest his loyal party service.

The Soviet Union invaded Afghanistan in 1979 and Wilson was under increasing pressure from rightwing associates to engineer a more robust American response. President Jimmy Carter ordered covert CIA support for the Mujahideen, but insisted it should not be traceable. Wilson, preoccupied with Israel (whose army had recently invaded Lebanon), took no action.

Then, glancing one evening at a news agency tape machine, he chanced on a harrowing description of the Afghan fighting. When a staff member of the defence appropriations subcommittee told him that $5m had been budgeted for the CIA's supportive action, he immediately ordered it doubled, a power within his remit that was routinely endorsed by his colleagues. They had no concept of what they had let loose.

The CIA did not want the money and was keen to avoid deeper entanglement in this thoroughly bewildering conflict. The agency's limited assistance was already channelled through the unsavoury regime of Ziaul Haq in Pakistan, and he, in turn, was playing off one Afghan faction against another. However, Wilson, who had become a close confidant of Zia's, embarked on a sustained campaign to force the CIA into wider action. With the help of the range of congressional networks he had established, and with the repeated intervention of Murtha and O'Neill, he got larger and larger sums added to the CIA budget and persuaded the subcommittee to mandate their use.

This cash was part of the “black budget” that funded intelligence operations — and therefore lay buried deep among the Pentagon's myriad appropriations — ensuring that Wilson's actions went through virtually unnoticed. Eventually, and astoundingly, his largesse amounted to $750m a year, 57 per cent of the CIA's entire covert operations budget.

Wilson became obsessed with the devastating impact on Afghan warriors of Russia's Mi-24 Hind helicopter gunship. With the aid of a maverick CIA executive, he embarked on a series of manoeuvres that were almost certainly illegal, including commissioning the Israeli defence industry to develop a lightweight anti-aircraft missile capable of being transported by mule.

He also contracted the Egyptians to manufacture bullets for the obsolete Enfield rifles then available to the Afghans and secured a secret deal with the Chinese to turn out copies of Soviet AK-47 assault rifles, Dashika machine guns, and RPG (rocket-propelled grenade) anti-tank missiles so that US involvement would remain undetected.

His greatest coup was to persuade Saudi Arabia to match the funds he pushed through the house appropriations committee, so that every $1m he drew from the US taxpayer became $2m when it reached the Afghans. This had the advantage that the Saudi cash came shorn of legal constraints.

With the connivance of Zia, weaponry poured into Afghanistan and Soviet casualties escalated. However, the 40th Army retained the advantage of the invincible Hind, with which it inflicted appalling casualties on the Mujahideen. The Reagan administration, by now deeply enmeshed in its disastrous machinations over Nicaragua, suddenly found itself under pressure from the extreme right to send modern, recognisably American weapons, to the Afghans.

The volume of US and Saudi money raised by Wilson made it ridiculous to disguise its origins and a distracted administration agreed to supply Stinger shoulder-launched anti-aircraft missiles. The weapon's warhead and launcher weighed only 30lb and could hit a target three miles away. After training, the Afghans began inflicting disastrous casualties on the Russians, averaging one $20m helicopter a day.

With the Soviet Union slowly disintegrating, President Mikhail Gorbachev called an end to this costly military adventure in February 1989. Wilson, who had managed to cover his tracks, despite making 14 official trips to the region, eventually told all to Crile and to CBS television.

Victors on the ground were the chaotic bands of tribal fundamentalists and their Arab co-religionists, trained in sabotage and terrorism by the CIA, armed to the teeth and awash with funds. In their own eyes, they had single-handedly beaten one superpower and were now preparing to take on another. The sky became darkened with the chickens that Wilson had reared.

In 2007, Tom Hanks played Wilson in the film, Charlie Wilson's War, directed by Mike Nichols, based on Crile's book. Wilson had a heart transplant that year.

His widow, Barbara, whom he married in 1999, and his sister, Sharon, survive him.—Dawn/The Guardian News Service