That's tricky. The men involved were ethnic Chechens, but they
had never actually been to Chechnya, which is part of Russia. Many
Chechens want Chechnya to be a separate country from Russia and
some have used terrorism to try to achieve this goal. Although the
men involved are known to have been strongly in favor of Chechen
independence, there's not an obvious reason why they targeted their
terrorism at the United States. Chechen terrorism is usually
targeted at Russia since the Russians are the ones who are refusing
to let them be independent.