Ecuador, one of the staunchest Latin allies of the United States, can be expected to take a turn to the left with the swearing in of a new president this week. This unhappy turn of events will open new avenues of contact and support for the Marxist states of Cuba and Nicaragua.

Among those in Ecuador for the change of government were U.S. Secretary of State George Shultz, Cuba's Fidel Castro, and Nicaragua's Daniel Ortega. Shultz kept a chilly distance from the others, who were clearly exulting over the altered political situation in Ecuador.Yet the U.S. must keep a strict hands-off policy, despite irritation at some stated goals of President Rodrigo Borja. The new Ecuadorian leader was chosen in a free and fair election. He is the third elected president in Ecuador since a military rulers returned the nation of 10 million people to democracy in 1979, after nine years of dictatorship.

The change in administration is particularly unsettling since the outgoing president, Febres Cordero, a U.S.-educated engineer, was a friend of America and was sometimes described as an ideological twin of President Reagan.

Borja has criticized Ecuador's pro-American foreign policy; promised to restore diplomatic relations with Nicaragua, broken under Cordero; vowed to abandon the free-market economy and regulate prices of goods; threatened to impose control on monetary exchange rates; threatened to reduce or halt payments on Ecuador's $9.3 billion foreign debt; and pledged to limit foreign investment in Ecuador.

There is no denying that Ecuador has economic troubles, due in part to the drop in world oil prices, and earthquakes that have devastated much of the country's oil production.

Yet a move to the left seems bound to do more harm than good both economically and politically. Other nations are finding that free markets tend to produce more prosperity.