captioning sponsored by macneil/lehrer productions >> lehrer: good evening. i'm jim lehrer. president obama called the gulf coast eco-disaster an "unprecedented crisis." he said the government and b.p. should have been better prepared for a worst case scenario. >> brown: and i'm jeffrey brown. on the "newshour" tonight: we have an update on b.p.'s efforts to plug the leak and excerpts from the president's news conference. plus, tom bearden looks at the spill from the waters of the gulf. >> this oil should float. it's not floating. why? and that's the $64 question from my perspective. >> lehrer: then, margaret warner details the administration's new national security strategy that emphasizes increased

diplomacy. >> we are no less powerful, but we need to apply our power in different ways. >> brown: and, as the 2010 book expo wraps up in new york, we look at new technology, shifting reading habits, and the future of the book. >> lehrer: that's all ahead on tonight's "newshour." major funding for the pbs newshour has been provided by:

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