Pope Francis

Crowds at Andrews Air Force Base cheered as the pope's plane touched down. Shortly after, President Barack Obama walked from the air base's terminal to the plane, where the American flag and the Vatican flag are waving.

The Pope is bringing his message to the world's wealthiest superpower and a country polarized over issues closest to his heart: immigration, social injustice and economic inequality.

President Barack Obama planned to greet Francis on the tarmac at Andrews Air Force Base upon his arrival from Cuba, according a rare honor to the pontiff.

The pope asked the Virgin to give Cubans "what they most desire and most need."

Two children gave him a copy of a century-old letter from islanders to Pope Benedict XV asking him to declare the Virgin the patroness of Cuba.

He now travels to the Cathedral of Santiago to bless families.

The Pope was delivering a subtle jab at the communist system during a Mass celebrated under the gaze of an image of Che Guevara in Havana's iconic Revolution Plaza.

The Vatican described the 40-minute meeting at Castro's residence as informal and familial, with an exchange of books and discussion about big issues facing humanity, including Francis' recent encyclical on the environment and the global economic system.

Fresh off his personal appeal to the U.S. and Cuban leaders to end their half-century of estrangement, Francis issued his plea to Colombia's warring factions from Revolution Plaza at the end of his Sunday Mass. Cuba has hosted peace talks for more than two years between the Revolutionary Armed Forces of Colombia and representatives of Bogota.

Francis said the talks face a "crucial" moment.

Pope Francis delivered the message as he opened his visit to the country amid great hopes that the key role he played in bringing about detente with the U.S. will result in changes on the island.

He will be offering a show of solidarity with Cubans and making clear that Hispanics in the United States are the bedrock of the American church.

The visit boasts several firsts for history's first Latin American pope: Francis will become the first pope to address the U.S. Congress and he will also proclaim the first saint on U.S. soil by canonizing the controversial (and Hispanic) missionary, Junipero Serra.

He wrote that "the church offers a path forward to peace, justice and true liberty," and added, "Not everything will be the same after he leaves."

Millions of Cubans hope those prove true when their author flies into Havana on Saturday as Pope Francis.

Across the island, Cubans are excitedly looking at the pope's 10-day trip to Cuba and the United States through the lens of his role as the mediator of detente between the two countries.