At a time when the United States is increasingly preoccupied with the economic challenge from Japan, I have been thinking hard about one aspect of the tragedy that killed 520 people in the crash of a Japan Air Lines plane earlier this month.

What has lodged in my mind were two paragraphs far down in the story John Burgess filed to The Post three days after the crash:

"Japan Air Lines President Yasumoto Takagi announced tonight that he intended to resign 'as soon as the situation has settled down.' He told reporters, 'I want to take responsibility.' Such resignations are common in the Japanese business and political world, where leaders are held to have ultimate responsibility for all acts of their subordinates.

"Takagi called on Prime Minister Yasuhiro Nakasone today to inform him of his decision. Nakasone reportedly admonished Takagi for the accident, saying that discipline at the airlines had become lax."

I wonder whether there is not a lesson for us in the way that the Japanese airline executive responded and the contrast to our way of handling such matters.

This is not an exercise of finger-pointing. I am not thinking of the specific contrast to the Delta Airlines crash at Dallas-Fort Worth Airport a few days earlier, or to the succession of accidents that have befallen Union Carbide at its plant in Institute, W.Va., since the disaster last year with the same company's subsidiary in Bhopal, India.

The top executives of those companies are still in place, but my point is a broader one. I wonder if we have not lost the whole concept of accountability at the top -- and with it, a sense of self-discipline and organizational discipline that is essential in a competitive world.

On several occasions in the past, going back to the Vietnam war period, I have written about the loss of the healthy tradition of a "resignation on principle." People simply have forgotten how to quit their jobs when they find themselves in strong disagreement with the policy they are being asked to carry out.

Cyrus Vance provided a rare exception to this rule when he quit as Jimmy Carter's secretary of state rather than attempt to justify the aborted Iranian hostage rescue effort, which he had opposed in the private councils of the administration. The more typical pattern is to disagree in private, support the policy or action in public, and then resign for what you describe as other reasons -- as David Stockman has just done.

But today I am talking about a different kind of resignation, the kind that is offered voluntarily by the head of an organization when there has been a costly, damaging failure of performance by his organization.

The examples that come to mind, unfortunately, all involved peple from countries other than our own. Takagi is one. Another notable one was provided by Lord Carrington, Britain's foreign secretary. Even though he was a favorite of Prime Minister Margaret Thatcher and a man of great ability, Carrington resigned the day after the Argentines occupied the Falkland Islands.

His ministry was responsible for the security of the islands and for the diplomacy that had failed to save them from invasion, so he stepped down. It was as simple as that.

Contrast that with the pattern of evasion, procrastination and repudiation of responsibility we see so often by senior officials in both the private sector and government in this country. The operative principle here often seems to be that it is always somebody else's fault.

The pattern is not confined to one business, one party or one administration. But present government has been as flagrant in denying any sense of personal accountability as any I can remember.

This is the first administration that tolerated having an indicted person -- former secretary of labor Raymond J. Donovan -- retain a position in the Cabinet. The list of those who fought to stay in their jobs, often with the president's indulgence, long after their unethical behavior, incompetence or chicanery had been exposed is lengthy enough to fill this page.

President Reagan himself damaged the principle of accountability in the uniformed services by claiming personal responsibility for the deaths of the Marines in the Beirut barracks bombing. That bit of premature grandstanding on his part prevented the Marines from dealing with the incident within their own chain of command, as they would otherwise have done. It damaged the system of accountability that all the armed services believe is essential to their own discipline and performance.

The relevance of all this to the controversy about the U.S.-Japan trade imbalance (a controversy that is sure to intensify when Congress returns next week) is evident.

We cannot compete unless we get tough. And the place we must get tough first is with ourselves. Leaders must set an example. And the example now being set by leaders in the United States, both in government and in business, is just not good enough.