The agreement between the United States and the Soviet Union to modernize their 21-year-old hot line is a good move. But it would be inaccurate to read too much into it: For instance, it does not signify a breakthrough on arms control or other major issues.
Certainly the hot line has needed updating. In this day of fast-moving events , what now exists is a relatively slow-speed teleprinter: In two years a much faster one is to be installed. The new one will also be able to show charts, maps, and drawings.
That's all to the good. But the need to take this step has existed for a long time, and it should be asked why the two sides have agreed on it at this moment.
One likely reason is that both the US and the USSR now want to be seen as willing to communicate with each other, but without appearing to back down from previous positions on major issues. (Witness the diplomatic minuet over September talks on arms control in space.) Modernizing the hot line is one way this appearance can be maintained.
The hot-line issue is not the only point of contact between Washington and Moscow. US officials say that quiet, behind-the-scenes contacts have been under way for sometime in an effort to keep the communications channels open. But additional public as well as private dialogue would be helpful.
Useful as modern machinery is, it is no substitute for better understanding, and therefore better communication in the broadest sense of the term, between the two nations.