Obamacare was enacted more than five years ago, and is now in its second year of nearly full implementation, but, in political terms, it is still not a settled matter. Republicans remain nearly unanimous in their opposition to the law, which continues to inspire widespread unease among the larger electorate. Many of its most important provisions — for instance, the individual mandate, the Independent Payment Advisory Board, and the “Cadillac” tax — are so unpopular that even many Democrats would like to see them repealed.