In January of 1941, Winston Churchill dined at a Glasgow hotel with his physician, Sir Charles Wilson (later Lord Moran ), and his secretary of state for Scotland, Tom Johnston. The other member of the party was Harry Hopkins, Franklin Roosevelt's redoubtable unofficial ambassador and the American president's most trusted adviser. Hopkins had been sent to investigate and report back in this hour of deadly peril for Britain, now standing alone in the battle against Nazi Germany.

At the Glasgow dinner he turned to the British prime minister. "I suppose you wish to know what I am going to say to President Roosevelt on my return. Well I am going to quote you one verse from that Book of Books in the truth of which Mr. Johnston's mother and my own Scottish mother were brought up: 'Whither thou goest, I will go; and where thou lodgest, I will lodge: thy people shall be my people, and thy God my God.'"

Then he added very quietly: "Even to the end."

"I was surprised to find the P.M. in tears," Lord Moran wrote in his diary. "He knew what it meant."

On Wednesday morning, a ceremony will be held on Capitol Hill to dedicate a new bust of Winston Churchill, to be on permanent display in the Capitol Building. House Speaker John Boehner, whose office conceived of the project, will serve as host for the occasion, advertised as bipartisan, with former speaker Nancy Pelosi and Sen. Harry Reid expected to attend.

The subject of Churchill busts has a certain resonance—recall the disappearance of the one that had adorned the Oval Office until Barack Obama's election. The planners of Wednesday's event—which came to pass via House Resolution 497 authorizing a Churchill bust to be placed in the Capitol—are assured that this one won't disappear. The resolution, introduced by Mr. Boehner and unanimously passed in December 2011, marked the 70th anniversary of Churchill's 1941 address to a joint session of Congress.

That address, barely three weeks after Pearl Harbor, drew a packed house which included Supreme Court justices and cabinet members, who hung on the prime minister's every word and gave him a roaring ovation. There had been worries that he might face a sparse audience, with members of Congress off for the Christmas holidays. It was a fear that appears ludicrous today, given the extraordinarily heroic stature America has long conferred on Churchill and all things connected with him. Not least those speeches.

Ted Cruz is only the latest in the lengthy line of politicians to employ or, more precisely, mangle one of the more renowned pieces of Churchillian rhetoric, as he did in his recent filibuster: "[W]e will fight on the beaches, we will fight on the streets, we will fight at every step to stop the biggest job killer in America." It doesn't quite have the ring of the original, you'll notice—those wartime lines that begin, "We shall defend our island whatever the cost may be" and that end with the stark, "We shall never surrender."

Still, the hold Churchill exerts on the American imagination is worthy of note and more—it's astounding. Astounding that 70 years after their delivery those speeches, their cadences and the dauntlessness for which they speak have lost none of their power. He brought ordinary language to extraordinary heights of eloquence. But there was little that was ordinary about the point of his renowned wartime speeches rallying the British to battle.

It is tempting, always, to think what Churchill would have said of today's isolationists who think and sound—particularly in America—so much like those of yesterday. "We shall see, " he wrote after the war, "how the counsels of prudence and restraint may become the prime agents of mortal danger; how the middle course adopted from desires for safety and a quiet life may be found to lead direct to the bull's-eye of disaster."

What would Churchill have said of the fantastic case of Edward Snowden, leaker of classified documents, embraced as a heroic figure both by the left and the right—but by none more than conservative television and radio stars unable to restrain their swooning over him, a hero on the lam they view as a selfless dissident struggling to save the nation from the evils of government secrecy. What might the prime minister have made of a journalistic specialty devoted entirely to the leaking of America's classified documents, as practiced by that model of brooding self-righteousness Glenn Greenwald ?

We can't know what the prime minister would have said but we can safely guess. Churchill was nothing if not a militant on matters of national security. When he received a plea in 1941 for more support for the work of the Bletchley Park Government Code and Cipher School, charged with the task of breaking enemy codes, he immediately ordered that the request be granted. The code workers must have all the help they wanted, and this was a matter of "extreme priority," he instructed his chief of staff.

To this directive he attached the note "Action This Day." Attendees of Wednesday's dedication ceremony will receive—compliments of the Churchill Centre, which donated the new bust—an Action This Day pin, replicating the color and type of the original note.

It is impossible to think of the ties that bound Britain and America—unforgettably echoed in those words of Harry Hopkins, and that Churchill himself felt so profoundly—without thinking of the August 1941 meeting between FDR and Churchill, their first, arranged in the deepest secrecy. Held off the coast of Newfoundland, the four-day visit concerned plans for postwar Europe. Its other vital aim was the expression of British-American solidarity—the U.S. had after all not yet entered the war.

On the day of the joint Sunday prayer service, with American and British crews packed tightly together on the HMS Prince of Wales, the American and British flags hung side by side. Side by side, too, the American president and the British prime minister sat singing the hymns well known to everyone present. Churchill had carefully selected them: "Onward Christian Soldiers," "The Navy Hymn," "O God Our Help in Ages Past." The same language, the same hymns, Churchill would later note. "It was," he wrote, "a great hour to live."