John McCain, the heroic naval officer held captive during the Vietnam War who ultimately rose to become one of the most prominent and well-respected voices within the Republican party, has died at the age of 81. 

In 2017, John McCain was diagnosed with glioblastoma, a malignant brain tumor for which he received radiation and chemotherapy. McCain represented Arizona in Congress for 30 years and made a name for himself opposing partisanship in defense of his own political convictions. McCain unsuccessfully ran for president in 2000 and 2008. He vehemently opposed orthodoxy and was considered a maverick in Washington. 

While battling cancer, McCain continued to be a force within the Senate, particularly when he returned to the chambers to cast his vote against a repeal of the Affordable Care Act. He adamantly opposed the presidency of Donald Trump, and rarely shied away from reminding his Republican colleagues of his dissent. 

The most famous prisoner of war in this country's history, McCain served in the Vietnam War as a Naval pilot and was held captive for five years by the North Vietnamese. After heroically returning and beginning his political career, McCain brought his military expertise to the Senate, becoming the chairman of the Armed Services Committee after Republicans regained control of the Senate in January 2015. 

Meghan McCain, John McCain's daughter, released a statement about her father's death and the legacy he's leaving behind. "He was a great fire who burned bright, and we lived in his light and warmth for so very long. We know that his flame lives on, in each of us," she stated.

Former President Barack Obama also released a statement in response to McCain's passing. "Few of us have been tested the way John once was, or required to show the kind of courage that he did. But all of us can aspire to the courage to put the greater good above our own. At John's best, he showed us what that means. And for that, we are all in his debt," he said.

Among many things, McCain will be remembered for his fearlessness, his dedication and his bravery.