Summits have led to major historic changes in this century - excessive German reparations after World War I that helped sow seeds of war II, tacit recognition of Moscow's Eastern European sphere, a new US-Chinese open door, US-Soviet detente, a slowing of the arms race.
One summit led to an increase in East-West tensions - over Berlin. One summit , in Glassboro, N.J., led to a rediscovery of the origin of the slang term ''booze.'' Another led Nikita Khrushchev almost, but not quite, to Disneyland.
Given this checkered history, would a Reagan-Chernenko summit be productive, risky, or neutral? Should it be meticulously negotiated and scripted, or should it have only a simple agenda? Should we rush to get it under way before the American election gives Mr. Reagan a new mandate, or a successor, on Jan. 20?
In recent months I've discussed summit realities with many specialists - including Soviet affairs authorities, arms control experts, and the man who carried a Reagan overture to Moscow last winter. These are some conclusions put forward by these Sherpas of the summit scene:
- Reagan and Chernenko are correct when they say an initial summit ought to be carefully prepared in advance. Mr. Reagan softened that stance at his June 14 press conference. But some key advisers say they still believe careful pre-negotiation is necessary. There are too many unknowns, too many bruised feelings, to make ''winging it'' advisable.
- Establishing personal rapport can take place in informal sessions around the fringes of the prepared, formal meetings.
- Later summits between the two leaders could be of the less-prepared, low-key, low-expectation, exploratory type.
- A custom of holding a get-acquainted summit within a few months of the selection of a new leader on either side could be built up over time. But a desire to create that precedent should not cause a rush to a summit now without careful planning.
- Mr. Reagan is sincere about wanting to go into the history books as a president who brought about a major reduction in the arms race. But there is also an element of election-year politics in his sharp turn toward wooing the Politburo leaders last winter.
- The Russian leaders have likewise been playing American election-year politics in recent months. But they have boxed themselves into a position where it appears they are aiding the man they didn't want to - Mr. Reagan - whatever they do.