Memory serves up a Bill Mauldin "Willie and Joe" cartoon from his World War II days. In the background is a general being saluted while in the foreground a blase' mess sergeant says, "Big deal, another danged mouth to feed." Such is Washington's reaction to the arrival of Mikhail Gorbachev. History's big occasion is our traffic headache.

History, if it permits irony, might want to pay as much attention to the inconvenience of Washingtonians as it does to the result of this summit meeting. The backdrop to the meeting between President Reagan and Gorbachev is, of course, the Soviet-U.S. rivalry, a usually cold, sometimes hot, competition that's persisted since 1945. It's a cliche' but nonetheless true that the ultimate stakes are the survival of the human race. Both sides have what it takes to kill us all.

But Washington at the moment is also ironic testament to the limits of power. Streets are blocked off and barricaded. Manhole covers are sealed, and windows in certain parts of town may not be opened. The police are everywhere, augmented by the Secret Service and the KGB. Gorbachev will hurtle through town in his own, Soviet-made, limousine. Very few people will see him, and he will see little of Washington and nothing of the rest of the United States. He -- and Reagan -- control vast and horrible arsenals, yet they are prisoners of the lone sniper with a mail-order rifle.

The precautions are necessary. Reagan was shot in 1981. President Kennedy, and later his brother Robert, were assassinated. Pope John Paul II was shot in Rome, Anwar Sadat was gunned down outside Cairo, and Indira Gandhi was killed in New Delhi. In Britain, Margaret Thatcher narrowly escaped a bomb planted in a hotel she was going to use. Olof Palme was shot to death on a Stockholm street, and Lord Mountbatten, a veteran of wars and narrow escapes, was blown to kingdom come as his yacht bobbed serenely off the Irish coast. None were victims of the Cold War.

In a way, the success of terrorists and assassins, and the precautions taken against them, are metaphors for a changing world. The Soviet Union and the United States, for all their raw military power, have less control over world events than they ever did. Once the twin kings of the postwar mountain, both now have to deal with a world where brute military power means less and less. Militarily weak Japan has a gross national product equal to that of the Soviet Union. Afghanistan eludes Soviet control and Vietnam went communist, U.S. B-52s notwithstanding. Gulliver has met the Lilliputians.

Terrorism and assassination are additional examples of the occasional impotence of power. Just the threat of them here has imprisoned Gorbachev, this most inquisitive of Soviet leaders. Unlike Khrushchev, who was able to tour the country (making a visit to an Iowa farm and to a Hollywood sound stage, for instance), Gorbachev will see nothing. In all but the most insignificant details, he might as well be in Geneva or Reykjavik. The chandeliers of power glitter the same the world over.

Americans have a naive, charming faith in the virtues of their country. Their boosterism is unbounded, and in the weeks preceding the summit there were suggestions galore of what Gorbachev could see or do: a visit to a supermarket, to a school, to the Reagan ranch or -- this one from Studs Terkel on National Public Radio -- to a black church in the South. These suggestions incorporate the hope for an epiphany, a sudden realization on Gorbachev's part that we are a wonderful society -- rich and just, free and exuberant. Walt Whitman heard America singing. We'd like Gorbachev to swoon to the tune.

The world does not work that way. Ideology and nationalism smother knowledge. Gorbachev is advised now by people who know the United States well -- former Soviet ambassador Anatoly Dobrynin, for instance -- yet his view of America remains both harsh and cliche'd. But the journalist, if not the tourist, knows the value of travel, of the chance remark heard on the street, of the conversation with the cab driver -- of the sight and sound of things that somehow provide either context or, better yet, refute myth and ignorance.

Gorbachev will not hear or see any of that. He comes to a peaceful city in temporary siege. His views, his ignorance, will go unchallenged by ordinary people, and he will return to Moscow as unsophisticated about America as he was when he left. The threat of the sniper has him pinned in his car. The world has changed and nuclear power is no longer supreme. The blockaded streets of Washington are more than just an inconvenience. They are a lesson.