"....The US took a benign view of this at the time. The operation was, after all, assisting in the fight against Communism. As Mr Mohamed's presence showed, those associated with the US military were providing assistance to Al-Kifah. The recruits received brief paramilitary training and weapons instruction in the New York area, according to evidence in earlier trials, before being sent to fight with Mr Hekmatyar. Even Sheikh Abdel-Rahman had, apparently, entered the US with the full knowledge of the CIA in 1990.
But by the mid-1990s, America's view of Al-Kifah had changed. It discovered that several of those charged with the World Trade Centre bombing and the New York landmarks bombings were former Afghan veterans, recruited through the Brooklyn-based organisation. Many of those the US had trained and recruited for a war were still fighting: but now it was against America. A confidential CIA internal survey concluded that it was "partly culpable" for the World Trade Centre bomb, according to reports at the time. There had been blowback.
How and why did the people behind Al-Kifah turn against America? The US cut off funding in 1991 to Mr Hekmatyar, both because the Russians had withdrawn from Afghanistan and because it had at last started to realise that backing Islamic fundamentalism was perhaps not the brightest idea the CIA had ever hatched. America had also gone to war against Iraq in 1991, and stationed troops in Saudi Arabia, outraging Mr bin Laden and other devout Muslims....read...."
Terror 'blowback' burns CIA - News - The Independent