The Cold War is long over, and with a better understanding of their mutual interests as well as the depth of their differences, the United States and Cuba officially restored their diplomatic relations Monday, July 20.

For the first time in 54 years, the Cuban flag was raised over Havana’s embassy in Washington, D.C., as onlookers demonstrated for and against normalization of relations.

Secretary of State John Kerry met with Bruno Rodriguez, Cuba’s minister of foreign affairs, at a joint news conference.

Said Kerry, “Today, with the opening of our embassies and a visit from the foreign minister, we are taking historic and long overdue steps in the right direction.”

The U.S. flag will not be raised in Havana until Kerry travels there on Aug. 14 for a ceremonial flag raising.

In 1961, under President John F. Kennedy, the U.S. severed ties with Cuba over that country’s alliance with the Soviet Union.

President Barack Obama has sought to improve relations with Cuba since he entered the White House. In December of 2014, it was announced that his administration was working on re-establishing diplomatic relations and re-opening embassies.

Last April, Obama met with President Raul Castro of Cuba face-to-face for the first time. Obama said although the governments will continue to have their differences, they agreed to continue to take steps forward that advance their mutual interests.

Kerry said the U.S. “welcomes this new beginning in its relationship with the people and government of Cuba.”

Many issues remain to be resolved, including Cuba wanting the end of the 53-year-old trade embargo and the U.S. wanting Cuba to improve on human rights and democracy.

Prominent Republican presidential candidates and some U.S. lawmakers have vowed not to revoke the embargo and pledged to put an end to Obama’s moves on Cuba.

Obama said the U.S. can’t keep doing the same thing and expecting a change. The U.S. removed Cuba from its list of state sponsors of terrorism in May.

“The significance of opening the embassies is that trust and respect that you can see, both sides treating the other with trust and respect,” Cuban diplomat Carlos Alzugaray said. “That doesn’t mean there aren’t going to be conflicts—there are bound to be conflicts—but the way that you treat the conflict has completely changed.”