Missouri’s Fourth Congressional District Vicky Hartzler was attacked.
"The writer, expert in biology, asks: why a Congress Representative would act "in support of the settlement enterprise".
Well, that has a long history. We could start with President John Adams who thought in a 1808 letter to Dutch Patriot leader and American immigrant François Adriaan van der Kemp that "I will insist the Hebrews have [contributed] more to civilize men than any other nation. If I was an atheist and believed in blind eternal fate, I should still believe that fate had ordained the Jews to be the most essential instrument for civilizing the nations" and added in a 1819 letter to Mordechai Noah that "I could find it in my heart to wish that you had been at the head of a hundred thousand Israelites indeed as well disciplined as a French Army-& marching with them into Judea & making a conquest of that country & restoring your nation to the dominion of it. For I really wish the Jews again in Judea an independent nation.'
In 1922, Congress approved of the Mandate for Palestine to reconstitute the historic Jewish National Home which, at that time, included Judea, Samaria and even Gaza in its territory. In 1924, Congress authorized the Anglo-American Convention for Palestine which also included that territory, with special emphasis on American citizens' rights. There are at least 30,000 American citizens living in the Judea & Samaria communities, excluding Jerusalem (see below).
Further, to "What U.S. or Missouri interests are served by this pro-settler activism?", I could add that economic interests of local industries are a possible factor as well as extending American values to the area for Jews and Christians and Muslims just like other foreign aid programs. Check the FB page of the US Consulate in Jerusalem to see how much taxpayer dollars go for "Palestinian Arabs". Also, Israel's security is well served by a Jewish presence in the hills overlooking Israel. Remove that and regional stability collapses.
And as for "Is she even serving the interests of American Jews, the majority of whom oppose the settlements while supporting Israel?" well, she is and I doubt the majority do oppose "the settlements" but simply want peace. Don't forget, "settlements" for Arabs and maybe Jews like the write also include 205,000 Jews who live in post-1967 Jerusalem neighborhoods. They are to be ethnically cleansed just like the Jews who lived in Judea, Samaria and Gaza were cleansed by Arabs during 1920-1948?