The governor of a large state,
if speaking for the E.U., risks not only undercutting federal officials who can
speak for the E.U., but also subtly orienting federal policy in the interest of
that state rather than the entire union. It is important, therefore, that the
president of the European Council be tasked with speaking publicly for the
Council, rather than usurped.
The full essay is at "Big States in the European Council."