During a war, a country needs to rally its allies. Unfortunately, in the midst of the global war on terrorism, we're finding ways to push some of our best allies away.

South Korea's an excellent case study.

That country's in a rough neighborhood, and it's logical to expect the biggest issue on people's minds would be North Korea's recent missile tests. That's a concern, of course. But South Koreans seem equally upset by the fact that they haven't been included yet in something known as the Visa Waiver Program.

You may be asking, "What's that?" Well, the VWP makes it relatively easy for visitors from 27 qualifying countries to come to the United States. They may stay for up to 90 days without having to obtain a visa.

Right now the program excludes South Korea, as well as other critical U.S. security and trading partners such as Poland, Estonia and the Czech Republic. They're excluded mostly because of a technicality. To qualify for the program, a country must bring its visa-refusal rate below 3 percent. But there's really nothing it can do to bring that number down, since American officials in each country are the ones who determine whether a visa request is accepted or denied.

Because their country's not in the VWP, each year hundreds of thousands of South Koreans must jump through hoops before they're allowed to visit the United States. They must appear in person at our embassy in Seoul, pay a fee, be interviewed and fingerprinted.

The arduous process sometimes causes mistakes. For instance, a few years ago a member of the Korean National Assembly, a man who had been invited here to deliver a speech at a university, was denied a visa.

It's no surprise that, in the face of all the hassles, fewer Koreans are coming here. In 2004, the number of South Korean visitors to the United States decreased by 5 percent, even as the total number of Korean tourists traveling abroad increased by 27 percent.

This doesn't make much sense. Politically, the United States and South Korea are as close as ever. Three years ago, despite some protests at home, the South Korean government sent 3,300 troops to Iraq at Washington's request. More than 2,000 remain there today, making South Korea the second largest non-U.S. troop provider after Britain.

Also, South Korea is our seventh-largest trading partner. But we may be putting that at risk.

Chinais a rising power and is taking steps to increase its trade with the South Korea. Two years ago, Beijing lifted visa requirements for most South Korean business executives. That will encourage greater Korean economic cooperation with China, and it's likely to take business away from American partners. We can't afford that.

The Visa Waiver Program hasn't been expanded since 1999, and in the post-9/11 world it's becoming outdated. The United States needs to be safer -- and it can be if we expand the program to include more of our allies. Congress should allow the Department of Homeland Security and the State Department to authorize a 10-year waiver of the 3 percent criterion if a country agrees to work with us to combat terrorist travel and enforce immigration laws.

After all, there's no evidence that South Koreans, Czechs, Poles or Estonians want to overstay their visas. Why would they, when their economies are humming at home? Most visitors simply want to be able to come, visit Disneyland, hammer out business deals and return home.

By giving them the ability to do so, we'll end up making new friends and stronger alliances -- two things we're going to need to prevail in this long war.

Edwin Feulner is president of The Heritage Foundation (heritage.org), a Washington-based public policy research institute and co-author of the new book Getting America Right.