Here's the Yemeni parcel bomb clarity you've been seeking: one of the two bombs intercepted by authorities was on a timer set to detonate as the plane flew over America's Eastern seaboard. But the bombers miscalculated.
The British police say the ink-toner-cartridge bomb was set to explode at 5:30 a.m. Eastern time, which the bombers calculated would have placed the plane over the Eastern U.S. Wrong, bitches. According to the Washington Post:
The same UPS flight can take different routes on different days, sometimes shortening the time needed to reach the United States. At 5:30 a.m. Oct. 29, the flight carrying the bomb was about 160 miles northwest of Quebec City, according to FlightAware, a Houston-based group that provides flight tracking data.
So, not only was the plan foiled—even if it had happened, it would have been an attack on Canada. And Canadians are not provoke-able.