“We are a small nation. Our military strength in proportion to the mighty armaments of modern nations can never be considerable. Our strength as a nation will depend upon our economic freedom, and upon our moral and intellectual force. In these we can become a shining light in the world.”

Source: 1962, Address and Question and Answer Period at the Economic Club of New York

Speech https://api.parliament.uk/historic-hansard/commons/1933/mar/14/supply#column_1820 in the House of Commons (14 March 1933)
The 1930s

Source: 1961, Speech to Special Joint Session of Congress

1960s, Farewell address (1961)
Context: We now stand ten years past the midpoint of a century that has witnessed four major wars among great nations. Three of these involved our own country. Despite these holocausts, America is today the strongest, the most influential, and most productive nation in the world. Understandably proud of this pre-eminence, we yet realize that America's leadership and prestige depend, not merely upon our unmatched material progress, riches and military strength, but on how we use our power in the interests of world peace and human betterment.

1900s
Context: When Mr. Cobden preached his doctrine he believed, as he had at that time considerable reason to suppose, that while foreign countries would supply us with our foods and raw materials we should remain the workshop of the world and should send them in exchange our manufactures. But that is exactly what we have not done. On the contrary... we are sending less and less of our manufactures to them, and they are sending more and more of their manufactures to us... Our existence as a nation depends upon our manufacturing capacity and production.

Speech in Glasgow (6 October 1903), quoted in The Times (7 October 1903), p. 4.

Some Reflections on Peace in Our Time (1950)

Sabhal Mòr Ostaig Lecture (December 19, 2007)

Presidency (1977–1981), Inaugural Address (1977)
Context: The world itself is now dominated by a new spirit. Peoples more numerous and more politically aware are craving and now demanding their place in the sun – not just for the benefit of their own physical condition, but for basic human rights.
The passion for freedom is on the rise. Tapping this new spirit, there can be no nobler nor more ambitious task for America to undertake on this day of a new beginning than to help shape a just and peaceful world that is truly humane.
We are a strong nation, and we will maintain strength so sufficient that it need not be proven in combat – a quiet strength based not merely on the size of an arsenal, but on the nobility of ideas.
We will be ever vigilant and never vulnerable, and we will fight our wars against poverty, ignorance, and injustice – for those are the enemies against which our forces can be honorably marshaled.
We are a purely idealistic Nation, but let no one confuse our idealism with weakness.
Because we are free we can never be indifferent to the fate of freedom elsewhere. Our moral sense dictates a clearcut preference for these societies which share with us an abiding respect for individual human rights. We do not seek to intimidate, but it is clear that a world which others can dominate with impunity would be inhospitable to decency and a threat to the well-being of all people.

1960s, Inaugural address (1965)