In addition to "presiding" over, and creating the worst U.S. economy since the Great Depression of the 1930s (double digit inflation!) the most horrible thing President Carter did was to stop all research on the "Neutron bomb." This was a weapon in which research had begun even before I served in counter intelligence/cryptography, back in "the dark ages" (1960s).
This weapon, if and when perfected and utilized, would only kill living things. Infrastructure would remain intact. I can think of many scenarios where a weapon such as this could have saved tens of thousands of American lives in the past 60 years. I urge President Trump to restart this research. Using our technology to protect Americans from terrorism, and enemies who wish to destroy Western civilization, is always justifiable.