Short time could be anywhere from 5-15 years. It took 25 years to get from the OK City bombing to the Capitol attack. But it only took about 5 years after OK City bombing before conservatives were complaining about the FBI unfairly going after militias.
Times change and so do laws and national focus.
Who on this forum thinks GW Bush could have shoved through DHS, TSA and the rest of the Patriot Act in August 2001? Not me. It takes something like Pearl Harbor, 9/11 or 1/6 to get government to move off its fat ass and take action.