SACRAMENTO Over the past year, Gov. Arnold Schwarzenegger has sought to position himself as a leader on climate change issues. He outlined a broad program to reduce air pollution during a speech at a United Nations summit a year ago and last week reached a publicity-generating agreement with British Prime Minister Tony Blair. The Republican governor now faces a dilemma that threatens to undermine his environmental credentials at the same time he is trying appeal to moderate voters as he seeks re-election. This month, the Democrats who hold a majority in California's Legislature plan to send Schwarzenegger a bill that...