In a move that has provoked conflict in Congress, the Bush administration has instituted a two-year moratorium on expanding national parks, arguing that its first order of business should be to clear up a $4.9 billion maintenance backlog at existing parks. Environmentalists and national parks advocates are up in arms over the moratorium. Less predictably, House Speaker J. Dennis Hastert (R-Ill.) is upset because he wants the federal government to buy former President Ronald Reagan’s childhood home in Dixon, Ill., and turn it into a historic site.