Watching reports of President Obama’s recent visit to Vietnam, I wondered why we fought a war there, beginning in the 1960’s. Many Americans and Vietnamese lost their lives. Others suffered injuries and emotional trauma.

Why? We are now forging economic and cultural ties with Vietnam, though it remains a country ruled by one party. It is not a democracy.

Other countries are not democratic. Yet we do not go to war with them. We have relations with most of them.

In the Cold War era, Soviet Russia was an undemocratic, communist nation. The danger from the Soviets was not imagined, especially in Europe. Yet, we found other ways to protect ourselves that did not include fighting a war with them.

We went to war in Vietnam because we chose to believe that losing Vietnam to communism was a danger to us. Other nations in the region, so we believed, would become communist, and, by popular definitions of the time, become our enemies also.

After losing Vietnam, we discovered how tragically wrong we were in our assessment.

Our involvement in Vietnam sprang, not from a threat to us, but from a blanket fear of communism. We failed to see the Vietnamese insurgency as a desire to be free of colonialism, as practiced by the French, whose place we took in entering the conflict. In the eyes of many Vietnamese, we also were imperialists.

We failed to differentiate between true threats and other movements, repugnant to us but not directly threatening us.