The question was not whether we should keep company with unsavory characters and impede on the governance of others, thats going to happen whether we do it or not. The only question is where their allegiances lay. That was the rule of the cold war. Jimmy Carter tried to ignore it and the Soviets made him look like a fool.
To make us love our country, our country ought to be lovely.
- Edmund Burke
In 1953 President Eisenhower followed the policy you recommend by directing the CIA to overthrow the democratically elected government of Iran and to install the Shah as absolute monarch. Previously he had been a constitutional monarch, sharing power with an elected parliament.
The Shah was never a popular dictator. The Iranians knew that we put him in power and kept him in power by helping to create and to maintain SAVAK, his secret police.
When the Shah was finally overthrow, the Iranians hated us, just as we would hate a country that imposed a dictator on us. The only thing Carter could have done to save the Shah was to occupy Iran.
President Carter had learned from the War in Vietnam that it is not a good idea to occupy a hostile population that is willing to fight back. President George W. Bush unfortunately did not learn that, and started expensive wars in Afghanistan and Iraq that he could not win.