Two weeks ago, “Bridgegate,” the scandal surrounding allegedly politically motivated lane closures last September at the Fort Lee, N.J., approach to the George Washington Bridge, was primarily a local political tempest whose headlines were believed to have come and gone. To be sure, the New Jersey Assembly transportation committee was conducting an investigation of the extremely disruptive lane closures, and the Port Authority’s Office of Inspector General was looking into it as well. But as of Jan. 7, interest in the cause of the GWB and Fort Lee traffic jams was confined primarily to a committee room in Trenton, the neighborhoods around the bridge and The Wall Street Journal, which smelled a rat and doggedly investigated the affair from the beginning.

Then came Jan. 8, when the words “time for some traffic problems in Fort Lee” converted the controversy into a full-scale, four-alarm national scandal and critical tests of the credibility of Gov. Chris Christie and the viability of his potential candidacy for president in 2016. “Time for some traffic problems in Fort Lee” was written in an Aug. 13, 2013, email from Christie’s then-deputy chief of staff, Bridget Anne Kelly, to David Wildstein, a Christie appointee to the Port Authority, who responded, “Got it.” Around three weeks later, two of the three lanes providing access to the GWB from Fort Lee were shut down without prior notice to local officials, creating a four-day traffic nightmare in Fort Lee that even impacted emergency medical services response times.