Before 1995, the federal government restricted speed limits to 65mph and lower (and prior to 1987, 55mph and lower). When those limits were raised or lifted, those opposing the change howled about how many additional Americans would die with higher speed limits.
The decline in auto fatalities (and pedestrian fatalities) has continued, even as speed limits went up dramatically in many states.
Correct! The 55mph law was first started during the gas crisis of the 70s. Its impact on traffic safety has been argued back and forth ever since, but so far there is zero concrete evidence that the increase in speed limits has caused a likewise increase in fatalities. (I have heard some good-sounding arguments that 55mph on long stretches of road is actually more dangerous than 70mph on the same, but I cannot find any studies to back that up, either.)
The decline in auto fatalities (and pedestrian fatalities) has continued, even as speed limits went up dramatically in many states.