AS THE pictures and stories flow in conveying the horror of the earthquake in Mexico, a kind of earthquake of feeling for Mexico is being registered in the United States. The Mexicans are proud, and they do not come running for other people's help when disaster strikes, and if they did, they might not come running immediately to the United States. If they did, however, they would find a large reservoir of compassion for a friend and neighbor in distress. Mexico is close enough and familiar enough and, most Americans know, important enough to make its current suffering echo keenly here.

The experts will now proceed to report how it was that this immense shudder of nature took place, and why it was that the Mexicans unfortunately chose to develop and populate an earthquake-prone region in a manner bound to multiply the damage once another shock came. No doubt there are some useful lessons for Mexicans but there are also some lessons for Americans. The geological structure which gave rise to this event extends up the Pacific Coast. Mexico's trial offers an opportunity for a kind of practice run for services and responses that Americans themselves might one day need, without warning, and for a contemplation of the policies and decisions that put large regions of the United States at similar risk.

What seems no less relevant to the scenes of suffering and devastation in Mexico is an awareness of the tremendous other unrelated difficulties the country was undergoing. Mexico has been "modernizing," that is, shifting an ever-faster- growing number of people into places, structures (physical and institutional), occupations and conditions of life under great strain. The earthquake, notwithstanding its terrible toll, may have directly affected the lives of relatively few Mexicans. But it has added to the immense burden Mexico was already carrying as a result of its passage into the modern age.

It goes without saying that the United States must be generous to a fault in responding to any requests for assistance that Mexico makes. But beyond the bulldozers and the emergency hospitals and the rest, this country ought to be prepared, in the large financial affairs that bind the two nations, to look beyond the technicalities of who owes what to whom and when.

Mexicans need some time, perhaps some months, in which to reorganize and take account of this catastrophe. It is not just the American government and the international agencies that should realize this is a moment to step outside routine. So should the private banks and businesses dealing with Mexico. The North American response now could set the tone of Mexican-U.S. relations well into the future.