More than any other figure who strode across the revolutionary stage, [Joseph] Warren gave his devotion to the American cause simply because he believed in it. Others believed as passionately, of course; but for Samuel Adams political agitation was a profession which had rescued him from a debtors’ prison; James Otis had deep grievances against the royal government because of their mistreatment of his father; John Hancock was a millionaire merchant who made much of his money from smuggling and owed the British Revenue Service over £100,000 in fines; as a lawyer, John Adams was naturally drawn into the political arena. Warren, as a doctor could have remained aloof, as many of his fellow physicians in Boston did. They were the only class in Massachusetts who were not pressured to join the cause.
— Thomas Fleming
Now We Are Enemies: The Story of Bunker Hill (1960; reissued 2010)