What’s the Baptist position on outlawing circumcision?
i) Many Baptists are dispensationalists. I assume they support the right of Jewish parents to circumcise their sons.
ii) Baptist theology also tends to accentuate the discontinuity between the old covenant and the new covenant, although there are many variations on this emphasis. Baptists who subscribe to the LBCF see more continuity than new covenant Baptists (e.g. D. A. Carson). Dispensationalists see continuity in terms of ethnic Israel's future restoration.
Considered in isolation, if you emphasize the newness of the new covenant, you might be more inclined to support a legal ban on circumcision. Circumcision null and void.
iii) On the other hand, Baptists also tend to stress separation of church and state, although there are variations on this emphasis as well. And Baptists who stress separation of church and state often ground this in their view of the old covenant. They say the old covenant in toto is obsolete. The OT theocracy was part of Israel’s unique, unrepeatable, cultic holiness. It represents a temporary stage in the history of redemption.
If you begin with that frame of reference, you might be inclined to oppose the state outlawing circumcision because you don’t think the state has the duty to regulate religion. That’s too theocratic. Rather, you’d support religious freedom. Individual conscience.