The latest lawsuit against former US secretary of state Henry Kissinger may well be dismissed on nuisance grounds long before it can force testimony from the man who once served as chief architect of American foreign policy. But it does raise an important issue which causes disputes among experts worldwide, and which requires some definitive guidelines. The suit, entered in US federal court, alleges Mr Kissinger was responsible for the 1970 killing of Chilean General Rene Schneider, the armed forces chief of staff. The leftist Salvador Allende had just won the presidency by a narrow margin, and General Schneider promised to support him as the democratically elected head of government. This was too much for Allende's right-wing foes, and some kidnapped the general in hopes of forcing a reversal of his position. Instead, he was shot in the attempt and died two days later. According to a television news report broadcast on Sunday, the botched kidnapping was financed by the CIA acting under instructions from president Richard Nixon and Mr Kissinger, then the White House security adviser. The general's family filed the lawsuit. As usual in such things, the truth is difficult to find. Mr Kissinger long ago denied any role in the kidnapping but clearly had some knowledge of the kidnappers. In past congressional testimony, he said all US support for the group was stopped two weeks before the crime took place. A TV news report unsupported by past investigations is a slender reed upon which to base legal action. Mr Kissinger may succeed in having it dismissed. But the case raises the issue of personal responsibility for official actions which may later be called crimes, including crimes against humanity. The US in particular resists letting its citizens be subject to such prosecutions, though it has no qualms about pursuing others - such as by seizing the president of Panama for narcotics trafficking. Better definitions of international crimes are needed, along with new agreements for dealing with them - even if the price includes more spurious lawsuits from those who feel aggrieved by alleged actions of other governments.