After decades as the crossroads of prairie populists and checkbook conservatives, Iowa has suddenly become solidly Republican like many of its Midwestern neighbors. It was one of four states — along with Kentucky, Missouri and New Hampshire — that flipped to complete GOP control in the November election, but Iowa’s rush of new legislation has been the most intense. In an all-night session last week, Iowa lawmakers approved a bill similar to one enacted in Wisconsin six years ago that strips most public sector unions of long-held collective bargaining rights, including health insurance. […] Among other items, Republicans also are...