WASHINGTON — President Bush today defended the Environmental Protection Agency’s decision to deny California’s bid to regulate greenhouse gas emissions from automobiles, saying that a national strategy toward climate change is more effective than a state-by-state approach. ‘The question is how to have an effective strategy,’ Bush said at a year-end news conference. ‘Is it more effective to let each state make a decision as to how to proceed in curbing greenhouse gases, or is it more effective to have a national strategy?’ Bush said. With the enactment this week of a landmark energy bill raising automobile gas mileage standards to 35 miles per gallon by 2020, Bush said, ‘We know have a national plan. It’s one of the benefits of Congress passing this piece of legislation.’ EPA administrator Stephen L. Johnson on Wednesday denied the state’s request to implement its own landmark law, dealing a blow to the state’s independent attempts to combat global warming and prompting an immediate vow from Gov. Arnold Schwarzenegger to take the decision to court. ‘The Bush administration is moving forward with a clear national solution, not a confusing patchwork of state rules,’ Johnson said in announcing his decision. […]