A Gigantic Boiler

I've been watching the 2nd season of Smallville on DVD through my subscription to Blockbuster Online. The other night, Lex Luthor quoted Winston Churchill. I Googled the quote and here it is (taken from an article at The Chuchill Center):

Silly people - and there were many, not only in enemy countries - might discount the force of the United States. Some said they were soft, others that they would never be united. They would fool around at a distance. They would never come to grips. They would never stand blood-letting. Their democracy and system of recurrent elections would paralyze their war effort. They would be just a vague blur on the horizon to friend or foe. Now we should see the weakness of this numerous but remote, wealthy, and talkative people. But I had studied the American Civil War, fought out to the last desperate inch. American blood flowed in my veins. I thought of a remark which Edward Grey had made to me more than thirty years before - that the United States is like "a gigantic boiler. Once the fire is lighted under it there is no limit to the power it can generate."

He said this in response to the attack on Pearl Harbor. It made me think of our war on terrorism. The terrorists lit a fire under "a gigantic boiler", and now they are seeing that "there is no limit to the power it can generate".