Story highlights CNN's Michael Smerconish said Trump's decision was motivated by "political calculus"

In commentary on CNN, Smerconish says move abdicates US leadership role in world

(CNN) President Donald Trump's decision to withdraw from the Paris climate agreement was a political move designed to "throw his base a bone," CNN host Michael Smerconish said in an on-air commentary Saturday.

"It was a decision of global importance, not made based on science and diplomacy, but one which appears to have been determined by a political calculus ," Smerconish said of Trump's announcement this week to pull out of the environmental agreement adopted by 195 nations in 2015.

"This decision was the delivery of a campaign pledge made to the 46% of voters who carried him to victory, especially in Rust Belt states like Pennsylvania, Michigan, Ohio and Wisconsin."

Trump's voters had "little show for their support" so far, Smerconish insisted.

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