Let the word go forth: Pax America is in style again.

Not since John F. Kennedy's 1961 inaugural message has any president restated America's "manifest destiny" so heroically as Jimmy Carter did in his call to arms at Wake Forest University in Winston-Salem, N.C., just prior to his going out to sea to review the Navy, an exercise that invariably intoxicates all commanders-in-chief.

In recent years, following Vietnam and other ill-advised U.S. interventions, there has been a tendency to remember Kennedy's grandiose words with a certain ruefulness. But when he took office that gusty January day 17 years ago, most Americans were thrilled (momentarily) at hearing him declare:

"Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe to assure the survival and the success of liberty. This much we pledge - and more."

After the cheering came the disastrous Bay of Pigs Invasion, the ferocious Vienna confrontation with Nikita Khruschchev, revival of the German crisis and erection of the Berlin Wall, the Cuban missile crisis of 1962, and then the first U.S. armed forces to Vietnam.

Nevertheless, a lot of politicians, apparently including Carter, still think Americans prefer bombast to quiet, patient, unexciting diplomacy. At Wake Forest, the President drew himself up and said: "For many years the U.S. has been a truly global power. Our longstanding concerns encompass our own security interests and those of our allies and friends beyond this hemisphere and Europe."

"We have," he proclaimed, "important responsibilities to enhance peace in East Asia, the Middle East, the Persian Gulf, and in our own hemisphere . . . We have the will, and we must also maintain the capacity, to honor our commitments and to protect our interests in these critical areas."

Finally, and pointedly, he said the secretary of defense, at Carter's direction, "is improving and will maintain quickly deployabel forces - air, land and sea - to defend our interests throughout the world." Shades of Lyndon Johnson.

What of the War Powers Act of 1974, which forbids presidential deployment of troops without the approval of Congress, except in an emergency like, say, Pearl Harbor? Every national poll shows that Americans are against going to war anywhere except in self-defense. The latest NBC survey, in fact, shows that even if Israel were attacked, only 4 percent of Americans would approve of military support if it involved sending U.S. troops.

The chief executive's rhetoric may appease the country's cold warriors for the nonce, but in the process President Carter is administering a public drubbing to candidate Carter. At Wake Forest the president lashed out at the "myth" that "our defense budget is too burdensome," although he himself, as a candidate, promoted that so-called myth.

During the 1976 presidential race, Carter repeatedly pledged to cut $5 billion to $7 billion out of the defense budget, which in that fiscal year was around $100 billion. Today, Carter's own defense budget calls for $126 billion, and is headed for even larger increases.

Both as a candidate and as a first-year president, Carter warned the nation against an "inordinate fear of communism," but now he is alarmed over an "increase in Soviet military power" and sees an "ominous inclination" on the part of Russia to intervene militarily in local conflicts.

That obviously was a reference to Ethiopia, which asked for and got Russian arms after it was invaded by neighboring Somalia, a former Soviet satellite. Moscow broke with Somalia when the latter used Russian equipment to attack Ethiopia. So far, at least, it hardly adds up to "ominous" Russian agression.

While Carter's speech suggests he no longer has much hope for Russian cooperation, it does not jibe with other statements to the contrary. Only last October, it will be recalled, the White House was delighted to announce that the United States and Russia had agreed on a joint Middle East peace effort. A month later, Carter was so encouraged by the progress of SALT II that he was predicting an agreement in a couple of weeks.

As to the good faith of the Russians, the administration just a few weeks ago sent Congress a detailed report rebutting charges that the Soviets had violated the terms of SALT I. Also, several days ago, the administration asked Moscow to open negotiations to outlaw the use of killer satellites in outer space.

When Carter went to sea after the speech, he boarded the aircraft carrier Eisenhower, named after the president who in 1953 said: "Every gun that is made, every warship launched, every rocket fired, signified in the final sense a theft from those who hunger and are not fed, those who are cold and not clothed . . . This world in arms is spending the sweat of its laborers, the genius of its scientists, the hopes of its children."