The ornate East Room of the White House was bathed in TV klieg lights and all three of the nation’s TV networks were beaming the president’s prime-time news conference live, coast to coast.As I rose from my front row seat, as Newsday’s young Washington bureau chief, I realized I was about to confront the president with a stunning discovery I had found that afternoon that would sound like a made-for-TV movie coincidence. Except it would put the president’s latest scandal into a context that hard-working, tax-paying Americans would find instantly infuriating.It was Feb. 25, 1974. While Washingto…