He said he was so annoyed by the way in which the report, the National Intelligence Estimate (NIE), completed in April, had been taken out of context that he had ordered the document declassified.
The report found that the US-led invasion of Iraq had given birth to a new generation of home-grown Islamic radicals spread across the globe, according to anonymous sources quoted by The New York Times, The Washington Post and other newspapers over the weekend.
Bush, answering a reporter's question at the White House after meeting with Afghanistan President Hamad Karzai, said that the US had been repeatedly targeted by terrorists long before the invasion of Iraq.
'We weren't in Iraq on September 11, or when they first attacked the World Trade Center (in 1993,) or bombed the (USS) Cole, or blew up our embassies in Kenya and Tanzania,' Bush said.
'My judgement is if we weren't in Iraq, they'd find some other excuse because they have ambitions .... They kill to achieve their objectives,' Bush said.
He said that before the invasion of Iraq, terrorist mastermind Osama bin Laden had used the US involvement in Somalia as an excuse to attract terrorists to the jihadist movement, and the Israeli Palestinian conflict.
'They used all kinds of excuses,' he said.
Bush said that the selected excerpts of the NIE released to reporters were politically motivated to undermine the White House during the upcoming November midterm elections.
He said the leakers were 'trying to confuse the American people about the nature of this enemy.'
He said he had ordered the document declassified so that everyone can read it and decide for themselves about the nature of the terrorist threat to the United States.
US President George W Bush insists the war in Iraq has made the US safer and brought democracy to the country. But the death toll of thousands of Iraqi civilians every month from religious and ethnic conflict and by terrorist attacks has led even world leaders such as UN Secretary General Kofi Annan to warn of civil war if things do not improve.