Senator Edward Kennedy, who President Obama called "the greatest United States Senator of our time," died today at age 77 after a protracted battle with brain cancer.

Though best known for his expansive body of work on U.S. domestic issues, he also lead Congressional efforts to right wrongs abroad by applying pressure to repressive regimes like the apartheid government in South Africa and the Pinochet dictatorship in Chile, denouncing war (in Vietnam and Iraq), and promoting peace. He was granted an honorary Knighthood by Queen Elizabeth II for his role in the Northern Ireland peace process, which was "tremendous" according to Tony Blair on MSNBC this morning.

But, more importantly, he serves as the model for public service and diplomacy. Despite being a frequent target of partisan attacks, Kennedy's legacy in the Senate is one of pragmatism, compromise, and, as countless colleagues and analysts have repeated today, unparalleled effectiveness. He stood above personal concerns despite suffering great personal tragedy, and, as an emotional Vice President Biden said today, "made his enemies bigger, made them more graceful, by the way he conducted himself."

His eulogy for his brother Bobby echoes today: "[he] need not be idealized or enlarged in death beyond what he was in life, to be remembered simply as a good and decent man, who saw wrong and tried to right it, saw suffering and tried to heal it, saw war and tried to stop it." It is a simple, definitive, and profound paradigm for effective public service and statesmanship and is the most fundamental lens through which we should judge all world leaders and their representatives. Blair also said today that Kennedy is "a great icon not only in America but around the world." I sure hope so.

Rest in peace Senator.

UPDATE: The S-G pays his genuinely heartfelt respects.