Friday May 13, marks the seventy-first anniversary of Winston Churchill’s first speech in the House of Commons as Prime Minister. It was a short speech, made as Nazi troops drove Britain’s armies from the continent and began their conquest of Western Europe. But it was memorable, above all for its peroration, in which Churchill offered only “blood, toil, tears and sweat” and proclaimed that the aim of his government was simple: “Victory – victory at all costs, victory in spite of all terror, victory, however long and hard the road may be.”

Churchill was no newcomer to war in 1940. His entire life had been shaped by it, from his start in the British Army, to his rise to fame as a war correspondent, to his leadership of the British Navy during the First World War, to his service in the trenches, to his struggle in the 1930s against appeasement. He both loved and hated war. He loved the individual glory of the small wars on Britain’s imperial frontier, but he hated the dull, inhumane slaughter of modern, industrial war. It was because he understood war so well that he tried so hard to stop it in interwar years.

For that, he had been called a warmonger. But as he delivered his speech on May 13, 1940, he was a vindicated visionary, the only hope for Britain and the democratic world.

Today, we remember Churchill as the greatest Briton of all, a leader of genius, and an unparalleled orator. He was all of that, but if we want to know how he rose to those heights, we should not just think of him in 1940. We should look back to his long struggle in the interwar wars when he tried, and failed, to rouse the British people. In 1940, he gave the lion’s roar. But for years before that, he explained why the lion had to roar. That explanation offers truths we would do well to remember today.

One of Churchill’s greatest speeches during this struggle came in 1934. His subject was simple: “The Causes of War.” In this broadcast, he dismissed the idea that the way to prevent war was to focus on teaching Britons to hate violence, for the threat to peace did not stem from Britain. It stemmed from “a nation which with all its strength and virtues is in the grip of a group of ruthless men preaching a gospel of intolerance and racial pride, unrestrained by law.” It stemmed from the nature of the Nazi regime. Americans would do well to remember, when we wonder at the actions of foreign regimes, that they behave as they do not because of our failures, but because of their own.

It was tempting, Churchill admitted, to believe that the best response was isolationism, to argue that Britain should simply turn its back on Europe. But Britain could not escape. Moreover precisely because it was wealthy, Britain was vulnerable. Churchill reminded the British people that “the more civilized a country is, the larger and more splendid its cities . . . the more it is vulnerable” to attacks on its homeland.

That was a lesson that the attackers of 9/11, and the many who have tried to emulate them, knew all too well. And like Britain, we too cannot get away, even if we wanted to: the German air force that even in 1934 worried Churchill has been replaced by missiles that can reach us in under an hour.

Churchill dismissed another of our conventional pieties, the belief that we should disarm in order to prove our sincerity, and to “set an example to others.” This was exactly the argument that the Obama Administration is using to justify ratifying the Comprehensive Test Ban Treaty, but it left Churchill cold. He pointed out that Britain had disarmed after the First World War, but this had not induced others to follow suit. More fundamentally, arms were not the cause of wars, and the lack of arms did not guarantee peace. If all gunpowder could magically be rendered harmless, the world would be at the command of the men with the largest clubs.

So if pacifist propaganda, isolationism, and weakness could not stop war, what could? Ultimately, Churchill argued, the problem was human nature: ending war would require “rais[ing] human thought to a higher plane.” But absent that utopia, the answer was to accept a truth that Churchill knew was “unfashionable, unpopular, unpalatable. But it is the truth.”

History taught that violence was a near-constant. The only intervals of peace came “after armaments in the hands of strong government have come into being ... civilization has been nursed only in cradles guarded by superior weapons and discipline.” His nightmare was a Britain shorn of that power, bereft of the means to protect the peace. With the U.S. now the world’s leading democracy, as Britain was in the 1930s, Churchill’s lesson applies to all Americans.

Churchill did not value the British armed forces for their own sake. He valued them because they protected a nation he cherished, values that he believed in, allies he supported, and a political system that he praised as the finest in the world. He regarded the Second World War as “the Unnecessary War,” even though it was the conflict that rescued his career.

We remember him with gratitude, but on May 13 we think of him as a leader in war. We should honor him for his offer of “blood, toil, tears and sweat,” but we should also remember for our own time the clear, unsentimental vision he brought to the cause of peace.

Ted R. Bromund is Senior Research Fellow in The Heritage Foundation’s Margaret Thatcher Center for Freedom.