Second, though your message has been blunt, your tactics have been politically shrewd. In 2006, you started a new organization to fight gun violence: Mayors Against Illegal Guns. You thought that mayors had the credibility to reframe the issue as one of crime control, rather than gun control. Mayors Against Illegal Guns now has more than 800 mayors, and nearly one million “active supporters.” It has lobbyists in Washington and elsewhere, and has had success resisting recent N.R.A. legislative initiatives. Its short-term agenda — ban assault weapons, require background checks for all gun sales, make gun trafficking a federal crime, and so on — is a good, sensible place to start regulating guns.

Third — and let’s not be coy here — you’re rich. The N.R.A. has an annual budget that is reported to be $300 million. In 2011, the combined budgets of all the groups trying to prevent gun violence came to around $16 million. The best-known of those groups, the Brady Campaign to Prevent Gun Violence, has seen its support and its funding dwindle in recent years. Meanwhile, the N.R.A. and its allies have done a brilliant job at pushing through laws that make it nearly impossible to prevent gun violence. There are more than 200 members of Congress who regularly get a perfect score from the N.R.A. It is going to take money to change that because money is what Congress responds to…

With all due respect, sir, what the country needs is your leadership on this issue. The sooner the better.