imminent:
"The imminent threat is that suddenly, this biological warfare lab, for example, could have been put to use."
Source: Interview on NPR's All Things Considered, NPR (6/27/2003).

(emphasis added)

Immediate:

"[N]o terrorist state poses a greater or more immediate threat to the security of our people than the regime of Saddam Hussein and Iraq."
Source: Testimony of U.S. Secretary of Defense Donald H. Rumsfeld, Senate Armed Services Committee (9/19/2002).

grave:

"Saddam Hussein's regime is a grave and gathering danger. It's a danger to its neighbors, to the United States, to the Middle East and to the international peace and stability. It's a danger we cannot ignore."
Source: Donald Rumsfeld Addresses the Conference of Army Reserve Operators, Defense Department (1/20/2003).

"There is also a grave danger that al Qaeda or other terrorists will join with outlaw regimes that have these weapons to attack their common enemy, the United States of America. That is why confronting the threat posed by Iraq is not a distraction from the war on terror."
Source: Remarks by the Vice President at the Air National Guard Senior Leadership Conference, White House (12/2/2002).

this ones a hoot

"In defiance of the United Nations, Iraq has stockpiled biological and chemical weapons, and is rebuilding the facilities used to make more of those weapons."
Source: President: Iraqi Regime Danger to America is "Grave and Growing", White House (10/5/2002).


this one had me rolling on the floor
"The history, the logic, and the facts lead to one conclusion: Saddam Hussein's regime is a grave and gathering danger. To suggest otherwise is to hope against the evidence. To assume this regime's good faith is to bet the lives of millions and the peace of the world in a reckless gamble. And this is a risk we must not take."
Source: Address to the United Nations General Assembly, White House (9/12/2002).

(emphasis added)