Recent terror: the Westboro Baptist Church (pictured), the people terrorizing abortion and women's health care providers, https://www.justice.gov/crt/recent-cases-violence-against-reproductive-health-care-providers
the guy waiting at the children's bus stop with a gun https://www.wbaltv.com/article/jden-mcadory-man-with-gun-severn-school-bus-stop-governor/43944583 (granted, dunno if he identifies as Christian)
Oh, and a little older: the KKK, a terror organization that explicitly identified itself as a protestant Christian organization. They and similar groups systematically killed and terrorized people throughout the south.
Of course, all those "6 Million Wasn't Enough/ Camp Auschwitz" guys are practicing terror against groups with an all-too recent experience of mass terror and existential threat: Jews, gay people, the Roma . . .
We've got plenty of homegrown, native born, and, yes, Christian terrorists.