Of all the complaints that have been made about the new federal healthcare law, the angriest have been against the law's "individual mandate," which requires everyone who can afford health insurance to purchase it or pay a fine. Starting in 2014, people who fail to buy in will be charged a tax penalty that will start at $95 a year and ratchet up to 1% of annual income for the more affluent. The fine will rise to at least $695, with a ceiling of 2.5% of income, by 2016. The mandate is a target not only of public resentment and political rancor but of myriad lawsuits and state legislation aimed at disabling it. Six states already have made it illegal to penalize a person for failing to get health coverage, and more are expected to follow suit; Republicans in Congress are trying to throw out the provision altogether. But many believe that in the absence of a mandate, the entire law could unravel.