Kennedy here references Francis Bacon’s Aphorism 129 of Novum Organum: Again, we should notice the force, effect, and consequences of inventions, which are nowhere more conspicuous than in those three which were unknown to the ancients; namely, printing, gunpowder, and the compass. For these three have changed the appearance and state of the whole world; first in literature, then in warfare, and lastly in navigation: and innumerable changes have been thence derived, so that no empire, sect, or star, appears to have exercised a greater power and influence on human affairs than these mechanical discoveries.
1961, Address to ANPA

“I can assure you that every degree of mind and spirit that I possess will be devoted to the long-range interests of the United States and to the cause of freedom around the world.”

John F. Kennedy

Acceptance speech (9 November 1960) http://www.jfklibrary.org/Research/Ready-Reference/JFK-Speeches/Acceptance-Speech-by-John-F-Kennedy-Hyannis-Armory-Hyannis-Massachusetts-November-9-1960.aspx <br class="br">1960

“I appreciate very much your generous invitation to be here tonight. You bear heavy responsibilities these days and an article I read some time ago reminded me of how particularly heavily the burdens of present day events bear upon your profession. You may remember that in 1851 the New York Herald Tribune under the sponsorship and publishing of Horace Greeley, employed as its London correspondent an obscure journalist by the name of Karl Marx.
We are told that foreign correspondent Marx, stone broke, and with a family ill and undernourished, constantly appealed to Greeley and managing editor Charles Dana for an increase in his munificent salary of $5 per installment, a salary which he and Engels ungratefully labeled as the "lousiest petty bourgeois cheating."
But when all his financial appeals were refused, Marx looked around for other means of livelihood and fame, eventually terminating his relationship with the Tribune and devoting his talents full time to the cause that would bequeath the world the seeds of Leninism, Stalinism, revolution and the cold war.
If only this capitalistic New York newspaper had treated him more kindly; if only Marx had remained a foreign correspondent, history might have been different. And I hope all publishers will bear this lesson in mind the next time they receive a poverty-stricken appeal for a small increase in the expense account from an obscure newspaper man.”

John F. Kennedy

1961, Address to ANPA

“These burdens and frustrations are accepted by most Americans with maturity and understanding. They may long for the days when war meant charging up San Juan Hill-or when our isolation was guarded by two oceans — or when the atomic bomb was ours alone — or when much of the industrialized world depended upon our resources and our aid. But they now know that those days are gone — and that gone with them are the old policies and the old complacency's. And they know, too, that we must make the best of our new problems and our new opportunities, whatever the risk and the cost.
But there are others who cannot bear the burden of a long twilight struggle. They lack confidence in our long-run capacity to survive and succeed. Hating communism, yet they see communism in the long run, perhaps, as the wave of the future. And they want some quick and easy and final and cheap solution — now.
There are two groups of these frustrated citizens, far apart in their views yet very much alike in their approach. On the one hand are those who urge upon us what I regard to be the pathway of surrender-appeasing our enemies, compromising our commitments, purchasing peace at any price, disavowing our arms, our friends, our obligations. If their view had prevailed, the world of free choice would be smaller today.
On the other hand are those who urge upon us what I regard to be the pathway of war: equating negotiations with appeasement and substituting rigidity for firmness. If their view had prevailed, we would be at war today, and in more than one place.
It is a curious fact that each of these extreme opposites resembles the other. Each believes that we have only two choices: appeasement or war, suicide or surrender, humiliation or holocaust, to be either Red or dead. Each side sees only "hard" and "soft" nations, hard and soft policies, hard and soft men. Each believes that any departure from its own course inevitably leads to the other: one group believes that any peaceful solution means appeasement; the other believes that any arms build-up means war. One group regards everyone else as warmongers, the other regards everyone else as appeasers. Neither side admits that its path will lead to disaster — but neither can tell us how or where to draw the line once we descend the slippery slopes of appeasement or constant intervention.
In short, while both extremes profess to be the true realists of our time, neither could be more unrealistic. While both claim to be doing the nation a service, they could do it no greater disservice. This kind of talk and easy solutions to difficult problems, if believed, could inspire a lack of confidence among our people when they must all — above all else — be united in recognizing the long and difficult days that lie ahead. It could inspire uncertainty among our allies when above all else they must be confident in us. And even more dangerously, it could, if believed, inspire doubt among our adversaries when they must above all be convinced that we will defend our vital interests.
The essential fact that both of these groups fail to grasp is that diplomacy and defense are not substitutes for one another. Either alone would fail. A willingness to resist force, unaccompanied by a willingness to talk, could provoke belligerence — while a willingness to talk, unaccompanied by a willingness to resist force, could invite disaster.”

John F. Kennedy

1961, Address at the University of Washington

“If I should lose on the real issues, I shall return to my seat in the Senate, satisfied that I had tried my best and was fairly judged. But if this election is decided on the basis that 40 million Americans lost their chance of being President on the day they were baptized, then it is the whole nation that will be the loser, in the eyes of Catholics and non-Catholics around the world, in the eyes of history, and in the eyes of our own people.”

John F. Kennedy

1960, Speech to the Greater Houston Ministerial Association

“I would hope that all educated citizens would fulfill this obligation — in politics, in Government, here in Nashville, here in this State, in the Peace Corps, in the Foreign Service, in the Government Service, in the Tennessee Valley, in the world. You will find the pressures greater than the pay. You may endure more public attacks than support. But you will have the unequaled satisfaction of knowing that your character and talent are contributing to the direction and success of this free society.”

John F. Kennedy

1963, Address at Vanderbilt University