By Sophie Tatum, CNN

(CNN) -- Sen. John McCain warned against giving into fear and turning toward "spurious nationalism" Monday at an event honoring the war hero's contributions to the US.

"To fear the world we have organized and led for three-quarters of a century," the Arizona Republican said, "to abandon the ideals we have advanced around the globe, to refuse the obligations of international leadership and our duty to remain 'the last best hope of earth' for the sake of some half-baked, spurious nationalism cooked up by people who would rather find scapegoats than solve problems is as unpatriotic as an attachment to any other tired dogma of the past that Americans consigned to the ash heap of history."

The remarks came after McCain was honored with the Liberty Medal by the National Constitution Center in Philadelphia, months after being diagnosed in July with an aggressive form of brain cancer.

Former Democratic Vice President Joe Biden, who is the chair of the Constitution Center, bestowed the medal on his former Senate colleague, a US Navy aviator who was captured and held as a prisoner of war during the Vietnam War.

In his own remarks, Biden nodded to McCain's diagnosis as well as his history serving in the US military.

"John, you have broken many times, physically and otherwise, and you have always grown stronger, but what you don't really understand in my humble opinion is how much courage you give the rest of us looking at you," Biden said.

McCain was elected to Congress in 1982, and over his decades in politics has served in both the US House of Representatives and the Senate.

"We live in a land made of ideals, not blood and soil," McCain said Monday, reflecting on his time in public service. "We are the custodians of those ideals at home, and their champion abroad. We have done great good in the world. That leadership has had its costs, but we have become incomparably powerful and wealthy as we did. We have a moral obligation to continue in our just cause, and we would bring more than shame on ourselves if we don't. We will not thrive in a world where our leadership and ideals are absent. We wouldn't deserve to."

McCain was honored with the medal "for his lifetime of sacrifice and service," according to a Constitution Center description of the event.

Former President Barack Obama tweeted Monday congratulating McCain on the award.

"I'm grateful to @SenJohnMcCain for his lifetime of service to our country. Congratulations, John, on receiving this year's Liberty Medal," Obama wrote.

McCain, who also serves as the chairman of the Senate armed services committee, shared a statement on the honor on Twitter: "I've been blessed to spend my life serving something more important than myself, of being a bit player in the story of America #LibertyMedal"

The evening was also filled with patriotic anecdotes and stories from McCain's personal narrative. McCain served in US Navy until 1981, and was famously a prisoner of war at Hỏa Lò Prison, nicknamed the Hanoi Hilton.

This summer, the Arizona senator was diagnosed with a primary glioblastoma, an aggressive type of brain tumor.

The-CNN-Wire

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