“Have you ever heard the roar of a jet fighter?”

Kiyokatsu Kikuchi has. “No words can describe it. When they’re flying directly over my house it feels like my head’s being split open.”

For 40 years this has been going on. Kikuchi, 67, lives near the U.S. naval base in Atsugi, Kanagawa Prefecture. He was moved at last to vent his rage in a letter to the Asahi Shimbun.

“I understand,” he writes, “that we need deterrence.” On the other hand, “There are schools here, there are hospitals … I pray for a world in which deterrence will no longer be necessary.”

Are we heading toward such a world or away from it?

Japan, known throughout history for its indomitable martial spirit, has, when not in the throes of war — mostly civil war; a nation chasing its own tail — been astonishingly pacific. Four hundred years of peace from the eighth to the 12th centuries, then another two-and-a-half peaceful centuries from 1615 to 1867, are remarkable achievements — as are the 70 years of peace since World War II.

In the mid-17th century there lived a very old lady named O-An who regaled children with tales of the wars she had known as a young girl. One of her reminiscences anticipates Kikuchi: “When they fired those cannons it was horrendous. The (castle) turrets would shiver and sway, and the very earth seemed as if it would split open. For the frailer-spirited ladies, that was enough to make them faint on the spot.”

Imagine the children listening in wide-eyed wonder as she relates, “The severed heads taken (from the enemy) were collected in the (castle) keep. We attached name tags to all of them, to keep track of whose they were.”

That’s war for you — ghastly, gruesome, inhumane, inhuman. And yet, peace can get under your skin after a while, if you’re cast in a certain mold. A frustrated and bored 18th-century samurai has left us this poem: “What a waste! / Born into times so fortunate / that I must die lying at home on the tatami!”

Vast changes are afoot in Japan. Under the leadership of Prime Minister Shinzo Abe the nation is moving from pacifism to “proactive pacifism.” What is proactive pacifism? Is it another form of peace, or another form of war? “We are resolved,” Abe declared in his speech last month to the U.S. Congress, “to take yet more responsibility for the peace and stability in the world.” Asian neighbors have not forgotten the last time Japan took major responsibility beyond its own borders, and they persist, 70 years after the end of World War II, in issuing shrill demands for “genuine repentance.”

In freeing the Self-Defense Forces to join Japan’s allies in military action anywhere in the world, Abe vastly expands his country’s potential international role. In promising the U.S. Congress to get the necessary legislation passed by summer, though the Japanese Diet had not even begun debating the matter, he implicitly attached his proactive pacifism to America’s self-perceived role as a global force for good.

Whatever element of truth there may be in that self-perception, it is certainly not the whole truth. Recent wars — in Vietnam, Afghanistan, Iraq — make a poor case for war’s ability to achieve desired ends. Deformed offspring of the Iraq War launched in 2003 to “help democracy and peace and justice rise in a troubled violent region,” as then-President George W. Bush put it, is the Islamic State group — “the most evil terrorist outfit in history,” according to the monthly Sapio.

Does the Islamic State group symbolize the existence of evil in the world, against which force must be used if good is not to be engulfed? Or does it symbolize the evil that force necessarily spawns? Is Islamic State an argument for pacifism or against it?

Philosophy aside, who, one wonders, is Abe’s “we,” as in “we are resolved”? The nation is aging rapidly. One quarter of its population is 65 or over; by 2060, 40 percent will be. Do the elderly provide the “boots on the ground” the U.S. expects of its allies? They do not. The young, then.

But Japanese young people, their numbers steadily diminishing, come across as decidedly unmartial. Shukan Kinyobi magazine polled 116 youngsters recently in Shibuya, Tokyo’s youth mecca, on how they feel about Japan’s new path. The sampling is small, but for what it’s worth, 87.9 percent said that Japan should not involve itself in its allies’ wars overseas, as against 9.5 percent who said it should. On rewriting the Constitution’s war-renouncing Article 9, 51.7 percent were against it, versus 16.4 percent in favor.

Is that the last word? Most of us want peace. Are we entitled to it? Does the nature of the world permit it? In 1939 Mahatma Gandhi, India’s and the world’s saintly apostle of peace, said, “Even if Hitler were so minded, he could not devastate 700,000 nonviolent villages. He would himself become nonviolent in the process.” Maybe, maybe not. History offers few corroborating instances.

Among Japan’s neighbors are a rising and muscle-flexing China and an erratic nuclear-armed North Korea. Diplomacy and soft power are fine weapons. Are they sufficient? Sapio, reporting from Vietnam, speaks in its March issue of Japanese journalists there being approached by locals: “Japan, help us!” Placards at mass demonstrations read “China back off!”; “Shame on you, China bully!” It’s tense, facing power without power.

The Japan-U.S. security alliance that permitted Japan’s postwar pacifism was always anomalous, as Kyoto Sangyo University professor Kazuhiko Togo explains to Shukan Kinyobi. In a nutshell: “American troops are obliged to shed blood for Japan but not vice versa. … Some within the foreign ministry have been calling for years for an end to that asymmetry,” as have some within the American establishment. The sea change underway may only have been a matter of time.

Can we close on an optimistic note? Here’s good news: For all the Chinese government’s strident playing up of Japan’s wartime atrocities, ordinary Chinese, looking beyond that, are seeing present-day Japan with their own eyes and finding they rather like the place. Nice people, interesting culture. Polling Chinese students of the Japanese language, the International Exchange Research Center, a private Japanese-Chinese think tank, found 70.1 percent of respondents feel close to Japan — up 21.5 points from 2005.

Polls come and polls go — how much are they worth? Nothing, maybe, but you never know. O-An as a young girl would probably have dismissed optimistic forecasts of peace to come as so much wishful thinking. Against all odds, she would have been wrong.

Michael Hoffman blogs at www.michael-hoffman-18kh.squarespace.com.