The next step should be obvious.
Boston, Chicago, and San Francisco should henceforth deny building permits, including permits for renovations, to all religious groups that do not support same-sex marriage fervently (enough). This would be Catholics, Orthodox, and Evangelical Christians, Orthodox Jews, and Muslims (at least). No more churches, synagogues, and mosques for these folks until they change their minds. No more Catholic hospitals or schools, and no expansion for existing ones. Shut down existing ones for minor building code violations, and do not approve any needed repairs.
Oh, and while we're at it - the name "San Francisco" was given by some intolerant, Catholic Spaniards and must be changed immediately.