WASHINGTON - President Donald Trump offered a preview of his re-election campaign playbook last year when he visited the building site of a multi-billion-dollar cracking (sic) unit in western Pennsylvania, hailed as one of the largest construction projects in the country. To Trump, it was a pitch-perfect example of a booming economy. Except today, the site sits largely empty, after the coronavirus outbreak forced oil company Royal Dutch Shell to halt construction. The project’s thousands of workers are now unemployed, adding to the nearly 3.6 million Americans who filed for jobless benefits in the last two weeks. The tension between...