Why does he invoke Milton's name in "London, 1802"?

This is one of Wordsworth’s political sonnets. Although he
does not refer specifically to any corrupt politicians, his references make clear that
politicians and the English public alike are subject to his anger and to his assertions
that there is a need to discover new and thoughtful leadership. At the time Wordsworth
wrote this poem, Milton had been established as one of the great English voices. His
most famous poem, "Paradise Lost", had been acclaimed as the most outstanding of English
epics. Wordsworth’s apostrophe to Milton therefore has the effect of appealing to one of
the greatest figures in the English tradition. It is likely that Wordsworth is thinking
as much of Milton’s connection with the causes of freedom developed during the
revolution and interregnum (1642–1660) as of Paradise Lost.