For a country that has no discernible seatbelt law, the Republic of Korea is nonetheless high on security. That much is obvious after the first three days of the Olympic Games. The Great Festival of Mankind, as the host country calls it, is giving a lot of policemen the chance to work overtime.

When they say "police force" in Seoul, they mean it. Some 120,000 patrolmen are on duty during the 16-day run of the Olympics, and that doesn't count the special commando forces who are unseen yet reportedly ready to climb down ropes backward and upside down, fully armed, and are bulletproof, bombproof and bribe-proof.

Manpower is no problem. You can't walk more than 100 yards in any direction in downtown Seoul without bumping into a police officer or a soldier of some type. The work can't be terribly exciting. As long as you have your 100 yards under control, all you can do is stand there and wait. It's like stakeout work, only outdoors.

The security, of course, is in answer to the potential of trouble. The Koreans have to always live with that potential hanging in the air. This is a country with China and the Soviet Union (Siberia) as neighbors as well as Japan _ and if you don't think that poses problems, consider the fact that each of these three has, in the past, taken its turn controlling Korea.

It is also a country that is still in the midst of a civil war that has been on hold for the past 35 years. There is a 212-mile barbed wire fence between the South and North, and no one can cross it unless he's a major general or higher and knows the right password. There are people living in the South who were born and reared in the North, and they haven't been back to their homeland for 35 years.

It's a lot like living in Central Park at night. South Korea is a sort of West Berlin on a larger scale. As Chun Sangjin, the deputy secretary of the Seoul Olympic Organizing Committee, put it, "We are constantly under threat. That is a fact. We cannot relax."

The last time the Koreans did relax was in 1910, when Japan, the winner of the Russo-Japanese war, decided to annex Korea as a colony and, among other things, erase the Korean culture from the face of the land and change its language.

For that reason, you can drive all day in Korea and never see a Toyota or a Nissan.

It took until World War II to get rid of the Japanese. And no sooner were they gone than there arose this problem of the estranged North - and all the ramifications that go along with communists living next door.

But the South Koreans can live with that. They weren't about to let that stop them from bidding for the Olympic Games, and, once they got them, to let that stop them from guaranteeing their peaceful passage. Or so help them.

Every Olympic venue is like a mini-airport, featuring a security check for all spectators. Buses bringing in teams and officials are routinely checked for anything suspicious with mirrors that are rolled underneath the chassis.

Police dogs regularly sniff out the main press center, and at the Olympic housing villages _ where officials, press and athletes live surrounded by the security of 12-foot-high chain-link fences with barbed wire on the top _ soldiers wearing full combat gear and carrying high-powered rifles patrol around the clock.

There is little Clint Eastwood involved in all this. The police do not walk with a noticeable swagger. The mood is more, "Go ahead, don't make my day." At the security gates the signs say, in polite English, "Your cooperation with security would be most appreciated."

If these Olympics don't turn out to be peaceful, it won't be from lack of trying on the Koreans' part. They're not fooling around. They've brought out all their big guns for this one. The best offense is a good defense.

The Games shouldn't get any more dangerous than your latest taxi ride _ which, it ought to be noted, is dangerous enough. If/and/or when the Koreans rid themselves of these oppression problems, they really should look into a seatbelt law.