The supreme irony of our times is that the victor in World War II is now petitioning the two defeated powers for help. The moral in this may be simply that no nation ever wins a war, and the euphoria of "victor" can be more threatening for the future than the bitter medicine of "defeat." TGermany and Japan, with big trade surpluses and comparatively modest inflation and unemployed, are being urged by Washington to expand, take in more imports by lowering their own tariff barriers and thereby stimulate a lagging world economy. Secretary of the Treasury W. Michael Blumenthal went on a mission to Bonn with the sole aim of persuading Helmut Schmidt's government to loosen up and bring the deutsche mark down to a reasonable level with the battered dollar.

Although Blumenthal tried to put a good face on it, the only immediate result was a rise in the decibels of acrimony between the two capitals. A report from Bonn tells of a truce to end the backbiting.

Special trade negotiator Robert Strauss has made two trips to Tokyo in the past 10 months. The first was ostensibly to discuss the Tokyo round of multinational trade negotiations in Geneva. But of more immediate concern was the charge of dumping brought against Japanese television manufacturers by firms in this country.

The second mission in December, was to try to reach as agreement over the package of trade concessions that Nobuhiko Ushiba had brought to Washington only to be told that it was inadeuqate. Strauss succeeded in patching up an understanding that both sides accepted. There remains, however, the charge brought by U.S. steel companies that rivals in Japan are being subsidized by government to export steel at unfair rates.

As America's pricipal ally in Asia, Japan deserves consideration beyond the outcry of protectionist voices. When he was in this country recently, former Sen. Mike Mansfield. U.S. ambassador to Japan, spoke some plain truths before the Japan, Society in New York about the status of trade and diplomacy between the two powers.

"The steps Japan has decided to take," Mansfield said of the package agreement worked out by Strauss, "entail genuine sacrifices, painful adjustment in wide sectors of its economy and significant risk. They were not easy or empty concessions . . . Many sectors of the Japanese economy are in trouble."

Those who know Japan well give two reasons for the booming Japanese trade surpluses. One is advanced technology, a technology based on a high percentage of corporate income devoted to research and development, in some fields exceeding that of the United States, which has long rested on a complacent sence of superiority. The other is a work of ethic in a tightly knit society with a national motivation to recover from the flat-out ruin of 1945. Per man-hour productivity figures in the past decade are in many sectors of the economy than double those in the United States.

While some of the same factors prevail in Germany, there the past and the dire aftermath of World War I haunt the present. Inflation in Germany is 4.5 per cent, lower thaninother industrialized countries. Any increase would be a reminder of the disastrous inflation of the mid-twenties, when prices went up 150 percent a day.

The choleric Chacellor Schmidt knows only too well the scare effect of rising inflation. His socialist government will be hard pressed by the Christian Democratic Union in the 1980 elections. An attractive candidate is emerging in Karl Karstens, currently president of the Bundestag, as the leader of the CDU, the largest party in the Bundestag.

American officials trying to persuade their opposite German and Japanese numbers to take some risks in trade and finance are confronted with the fiscal status at home. President Carter has put the budgetary deficit at $62 billion for fiscal '79, but with so-called "off budget" items it is likely to be around $74 billion. And the dollar continues its downward spin.

Deeply disturbing to American allies abroad is the growing U.S. depenence on imported oil, as all efforts to reach an energy compromise have failed and pleas for conservation are ignored. The Department of Energy puts the share of imported oil today at 48 percent, rapidly approaching 50, with no relief in sight. Nearly half comes from the Middle East.

That serves to keep oil prices up and enlarge the difficulties of nations such as Japan who are entirely dependent on imports. It puts the teacher preaching an economics lesson to a friend and allky in a dubious position.