Alana Tummino is head of the AS/COA Cuba Working Group and senior director of policy at Americas Society/Council of the Americas. She is also a senior editor of Americas Quarterly magazine. The views expressed are the author's own.

(CNN) Fidel Castro's passing marks the end of an era that divided and separated the Cuban people. His death is deeply personal -- both for Cuban exiles in the United States and for Cubans on the island. Supporting policies that promote continued engagement between the United States and Cuba becomes even more important now.

True, Castro has not formally been at Cuba's helm for a decade. But his ever-present influence was felt through public appearances, grand speeches and in the landmark moments of Cuban politics, even attending Cuba's Communist Party Congress deliberations as recently as April. And his presence is physically all around you walking the streets of Havana. From signs and billboards, to painted slogans on the sides of concrete walls and buildings.

Lauded as much for his country's social gains in education and health as demonized for his human rights record and his tight grip on freedom of expression, the reactions to Castro's death mirrored these divergent views: tears and mourning from some on one side of the Florida Straits, and celebratory parades on the other.

For others, in practical terms, Castro's passing means life goes on as usual. Speaking with a friend and small-business owner from Havana the morning the news broke, she told me that her world is unchanged in Cuba, but that "we now have much more fear from what's to come when the new president of the United States takes power than from the passing of Fidel."

And for many of us who have been traveling to the island often in the past few years, attention is now turned to two focal points: the incoming US administration's policymaking toward Cuba, and Castro's brother Raúl Castro.

Raúl took the reins of power from an ailing Fidel in 2006 , and formally assumed the presidency in 2008. He launched an ambitious economic reform agenda to save an ailing economy, changing the way the traditional socialist economy was run. Implementation of many reforms has been slow, but the country would have to open more to the international economy for foreign investment, would allow for greater private sector activity in a number of categories, and would begin a process of decentralizing key sectors such as agriculture.

Couple this with the numerous rounds of reform and regulatory changes from the United States that significantly opened up travel, remittances, business activity, and the re-establishment of diplomatic relations in Havana and Washington, and we've entered a new and historic era of bilateral relations.

Raúl Castro is scheduled to step down from the presidency in 2018, in a gradual transition of power that will mean no Castro brother at the helm for the first time in 59 years. And it appears the country will continue to orient itself in this reform vein. Sluggish GDP growth and a struggling economy means the country cannot turn its back on its need for opening its economy and trying to attract greater investment.

In the country's latest "Portfolio of Investment Opportunities," released in November, there was a wish list of 395 projects totaling $9.5 billion of foreign investment. The money has been slow to trickle in, due to a range of less-than-ideal investment terms. But in our many trips to the island it is clear that companies from around the world are looking to invest in Cuba before restrictions are fully lifted from the United States. A range of international leaders have tried to exploit that advantage throughout the years with growing political and commercial ties between Russia, China, and European and Latin American countries.

And across the Florida Straits, I believe that the incoming administration has an opportunity to continue the process of normalization with Cuba at a unique and critical time.

Turning back travel, remittances, greater support for the Cuban people, and commercial engagement will hurt the very people who sanctions aim to support. Limiting the flow of remittances, which support families and entrepreneurs, and ending the ability of US travelers to visit the island and stay in privately rented homes and eat in "paladares" would dramatically alter the economic agency many Cubans now have from this new opening. From a commercial perspective, US companies will be on the sidelines as the rest of the world enters the market. It would also put the United States in a difficult position in promoting human rights and solving outstanding issues, such as the resolution of claims if we no longer have a formal diplomatic channel to do so. And it would once again alienate the United States geopolitically, especially in our policymaking in Latin America.

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A majority of Cuban-Americans in the United States support the process of US-Cuba normalization and 97% of Cubans on the island think normalization between the two nations is good for Cuba.

It is not often we can say we are at a historic crossroads, and yet the decisions of the next months will have a profound impact on so many people's lives. With Castro's passing, I hope that we see continued dialogue and engagement between our two countries that best serves the interests of the people on both sides of the Florida Straits.