[W]hy do we associate Contractualism with Anarchism, where there is extraordinary demand for the state, instead of associating Contractualism with Nationalism where there is almost no demand for the state?
Anarchism evolved in the middle east, in eastern european borderlands(owned but unregulated territories), and in western european ghettos(walled subcultures).
Contractualism evolved with near kin relations in the North Sea. (Frisia, England, Denmark, Norway, Sweden, and then germany and east)
You can only have contractualism under nationalism. Othewise you must have statism.