In the nearly 3 weeks since Joe Biden announced that Harris would lead diplomatic efforts to tackle the root causes of migration, the White House has repeatedly been forced to defend her and clarify that her role is focused on the Northern Triangle, rather than the Mexican border.

"The Northern Triangle, which I'm sure you're aware of," White House press secretary Jen Psaki said last week, "is not the same as the border."

Harris, for her part, has not held a public news conference to address the surge in migrants at the border, nor commented on when she'll visit Central America.

"People will hear from her soon," Psaki told CNBC.

According to experts in Washington DC, Harris' role is a politically sensitive one that will require a "whole of government" approach.

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"It's a very tough assignment. It's an extremely complex and difficult issue," said Michael Shifter, the president of the Washington DC-based Inter-American Dialogue. "It carries its risks for her."

It's a very tough assignment. It's an extremely complex and difficult issue. It carries its risks for her. This will be a test of her diplomatic abilities, which are less developed, and which will be important to be able to come up with an effective solution to this problem.

"If the situation continues to get worse and you don't see any improvement, this could be a liability," Shifter added in a conversation with LPO. "This will be a test of her diplomatic abilities, which are less developed, and which will be important to be able to come up with an effective solution to this problem."

On the other hand, Shifter said that the choice of Harris for the role sends a "powerful message" to the region and could allow her to demonstrate her capacities and talents, while at the same time not coming into competition with senior state department officials.

"It's clear she's in charge. I think she coordinates very well with the State Department and with Zúñiga (Ricardo Zúñiga, the State Department's Special Envoy for the Northern Triangle) and the rest of the team," he said. "As VP, she has the stature and authority to really oversee US policy."

A Mexican National Guard looks at local residents crossing the Suchiate River, near Ciudad Hidalgo, on the Mexican border with Guatemala

AP

Tony Payan, the Director of the Center for the United State and Mexico at Rice University's Baker Institute for Public Policy, said that the overarching aim of addressing the migration issue in Central American source countries is itself politically difficult within the US, particularly given the sizable investment required for the policy to be effective.

"I don't see much stomach in the United States for such efforts. Americans don't really want to invest and pay for that. Most people think that our needs our large enough that they ask why we should be sending $4 billion," he said.

"There needs to be political will to invest in that region so that they create their own economic development dynamics. Then people do not have an incentive to leave," Payan added.

Additionally, Payan said that the choice of Harris for the role offer a stark contrast to the "chaos" of the Trump administration.

"Before, there were disparate interest and personalities, and a lack of discipline. Everybody was pulling in their own direction, trying to please the president," he said. "There was only one person to please, and that was Donald Trump."

"If he designated Kamala Harris to lead these efforts, there probably isn't going to be that sort of chaos and disorder," he said. "She is in charge."

However, Payan said many questions remain unanswered.

"The details of what exactly she's going to try to accomplish are not out yet in full. We have bits and pieces, but we don't yet have a full idea of how and what she intends to accomplish, and how she will accomplish that," he said.

On Tuesday, a number of Republican politicians led by Congressman Chuck Fleischmann write a letter urging Harris to visit the US-Mexico border to see the issues firsthand.

"There is no substitute for seeing overcrowded migrant facilities in person and speaking directly with our border agents and officers who are dealing with this crisis on the human level every day," the letter said.

"We are greatly concerned about the Biden administration's ability or willingness to respond to this humanitarian crisis when neither the President nor the Vice President has gone to the Southwest border to assess the crisis," the letter added. "We invite you to make this journey to the southern border and to work with congress to find solutions to mitigate this humanitarian and national security crisis in order to protect our nation."