Among our conservative fire-breathers, Ronald Reagan comes closest to grasping what's happening. After decades of Evil Empire-bashing, he's open enough to the evidence of his senses to admit the possibility we've won a major round.

Not so his comrades. They're like their absolutist cousins on the left who found it impossible to oppose the Vietnamese war without hailing the communists as brothers and deciding we didn't really need an army.

Aside from INF treaty and summit chit-chat, Reagan has avoided dealing with Gorby, however. He exerts little influence on the staff regents who run his government along orthodox, take-no-prisoners lines.

People are smarter than cold-war theologs think. It's the politicians who either go crazy or fishing. Even at the depths of Vietnam disillusionment, most Americans wanted adequate defense. Nixon-Brezhnev detente seduced politicians, not normal folk.

Graham T. Allison Jr., dean of the Kennedy school at Harvard - both names in his title drive right-wingers bonkers - argues in the fall "Foreign Affairs" that we owe it to ourselves to test how far Gorbachev is willing to go.

This can be done, he says, without risking any vital interest. In particular, challenge Gorby with concrete proposals on his offer to publicly inventory his troops in Europe and draw them down asymetrically. Another area for testing: sealing off Central America from outside arms.

With a presidential campaign centered on the Pledge and who looks sillier driving tanks and-or 18-wheelers, we're unlikely to respond soon, but we should. Michael Dukakis talks about beefing up conventional forces, without the foggiest notion of the cost. We've relied on nukes not because we like them but because they're cheaper.

Neither candidate seems to accept the fact it will cost upwards of $40 billion to modernize the land-based missile force with the only logical system, Midgetman or a variation. Whatever happens in START, such upgrading is overdue.

Testing Gorbachev should begin at once. That doesn't require giving away the store. Americans are a practical, hard-headed electorate, despite the nutty people we're sometimes reduced to choosing. This country will support adequate defense through years of parleying for lasting peace. We've proven that. It's what George Kennan told us in the beginning the Cold War was about.