The announced departure of the head of Latin American Affairs of the State Department, Arturo Valenzuela, has given rise to a debate in Washington as to who should replace him and whether there should be a U.S. policy change regarding Latin America. Chilean-born Valenzuela, a Georgetown University professor, confirmed in office in November 2009 after a long struggle for Senate ratification, has announced that he will leave his position in a few weeks to return to academic life. The officer has been the target of harsh criticism by congressional Republicans.

His sudden departure has unleashed debate as to whether he should be replaced by a career diplomat, who would have more experience and a better chance at Senate confirmation, or by another known politician, like Valenzuela, who would have the advantage of being closer to the secretary of state and the White House.

Among career diplomats, legislative and diplomatic sources tell me that the names most circulated as possible successors to Valenzuela are Ambassadors William Brownfield and Anne W. Patterson.

Brownfield is the head of the State Department Bureau of International Narcotics and served as ambassador to Colombia, Venezuela and Chile. Patterson was ambassador to Pakistan, acting ambassador to the U.N., also served as ambassador to Colombia and El Salvador, and, in addition, was second-in-command for Latin American affairs during the mid-1990s.

But the problem is that Brownfield was named only four months into his position in the Bureau of International Narcotics, which has the same rank as Valenzuela’s position in the State Department bureaucracy. To remove him at this time would send an unmistakable message to the U.S. anti-drug bureaucracy, so some of his colleagues tell me.

And Ambassador Patterson is actually among the most important officers in charge of U.S. relations with Egypt, and would probably be appointed ambassador to Egypt, currently a priority in U.S. foreign relations.

It will not be easy to take either of the two from a present assignment, diplomatic sources assure me.

Other career officers mentioned are the ambassador to Thailand, Christy Kenney, who has served as ambassador to Ecuador, and also was outstanding in Argentina and Jamaica, and is, furthermore, Brownfield’s wife; Roberta S. Jacobsen, present second-in-command of Latin American affairs at the State Department, who was director of Mexican affairs, holds a high position in the U.S. embassy in Peru and was coordinator of Cuban affairs; and present ambassador to Colombia, Michael McKinley.

There are fewer choices among the known politicians who are not part of the State Department bureaucracy. Two of the main candidates for the position — past advisor to the White House on Latin American affairs, Nelson Cunningham, and present sub-secretary of U.S. Commerce, Francisco Sánchez — have told several friends they are not interested in the position.

Supporters of the idea of appointing a political, rather than career official, argue that some of the most critical issues in the relationships between the U.S. and Latin American — like the free trade agreements with Colombia and Panama, which have yet to be ratified by the U.S. Congress — require the designation of someone with good political connections in Washington, more than a vast knowledge of the region.

But supporters of naming a career official say that the Obama administration should avoid another long political battle with Congress, like the one it faced to realize the confirmation of the Valenzuela post two years ago. Now that Republicans have increased their congressional representation, hard-line Republican senators, like Jim DeMint of South Carolina and Marco Rubio of Florida, will feel even more emboldened in blocking the nomination of a Democrat from the center-left for this position, say well-placed sources from both parties.

My opinion: If there are no surprises, it is most probable that Valenzuela will be replaced by a career diplomat from the State Department — as time passes, Brownfield seems the most likely, because, among other reasons, the Obama administration will need the officer who occupies Valenzuela’s chair to be confirmed by the Senate as soon as possible, in order to begin preparation for the Summit of the Americas to be held in Cartagena, Colombia, in April 2012.

Will anything change in U.S. policy toward Latin America with the appointment of a new head of Latin American affairs? The ideal would be an affirmative answer. In a future column, I will tell you why.