Some years ago Governor William Donald Schaefer of
Maryland expressed
his support for retrocession, which would (further) glorify the great
state of Maryland.
The founders, however, (who were
continentalists) feared the jurisdiction of the states, remembering how
the Pennsylvania Executive Council had refused to protect Congress
during the mutiny of 1783.
I suppose the Federal government could retain jurisdiction for
certain purposes, even after retrocession.
Yes. Congress would retain legislative jurisdiction, to enact laws for
the residents, just not remove their Maryland citizenship, which
entails the rights to vote and hold office in Maryland. The Maryland
Legislature would not have jurisdiction to enact coercive legislation
for residents of DC, other than for voting. Laws for DC residents on
crime, police protection, tort, probate, family, contract, traffic, or
whatever, would still be under the legislative jurisdiction of Congress
or the DC government it establishes.