Will we ever learn?
Guy "Guido" Fawkes, an Englishman who converted to Catholicism as a teenager in the time when Catholicism was no longer the state religion but a proscribed and persecuted one, and then went to fight on the side of the empire that had tried quite hard to invade and conquer England when he was eighteen, came back with explosives training and joined an attempt by a radicalized member of an old ruling dynasty (whose father had been arrested and tried for harboring Catholic clerics due to fears that Catholics were supporting and aiding said foreign invasion) to destroy the British government in protest against the Penal Laws that to their disappointment had not been ended by a new administration as expected.
The plot only failed because someone among of the plotters had qualms and in effect whistleblew upon themselves to warn away a sympathizer in the government before the event, followed by the discovery of the planted explosives and the sapper himself in the course of searching the unsecured building on November 5th, 1605.
Re-authorization of judicial torture by executive fiat, which had been banned in the interrim since the Armada, didn't didn't actually work to yield any of the other conspirators, although prototypical police work - and a possible double-agent - did. That is to say, Fawkes didn't reveal anyone who might have another bomb ticking away in another undetected rented storage unit somewhere near government center, until after it would have been too late.
It did however eventually provide more suspects to torture and execute and validation of all the fears of the majority Protestant population and leadership regarding Catholics being dangerous traitors, leading to more repression justified as a reaction to the Gunpowder Plot.
The people calling today for more torture of suspects and persecution of Muslims in America as a result of the horrible but not unprecedented fragging at Ft. Hood, TX, on November 5th, 2009, ought to see the parallels, have little-to-no excuse not to, but almost certainly won't if they haven't yet.