At a news conference with the aura of a campaign rally, Cook County Board President Todd Stroger on Tuesday defended his preservation of a controversial sales tax increase and accused would-be repealers of political grandstanding. During the half-hour session at Provident Hospital -- one of the county's three public hospitals -- two ministers and a political organizer flanked Stroger. They praised his leadership, while hospital employees cheered on Stroger and his backers. "You did a bold thing, and I'm here to tell you as a representative of the community [that] you did the right thing at the right time for...