Blake openly conveys his political views, opposing government control, and linking to the theme of corruption that is included throughout the poem; as the word "chartered" connotates structure and restrictions, Blake introduces the idea that nature itself is restricted, hyperbolically heightening the extent of limitations enforced by the government
The line only has 7 beats in it, unlike the rest of the poem which has iambic tetrameter (only 8 beats per line) The broken number of beats shows how the inhabitants of London are broken along with their government which is ruining their lives.
epetition of 'every' and 'cry' develops the sense that Blake's London is a tortuous and agonising place in which to live. The sense that everybody, regardless of age, is living in this dystopian city pervades.
people trapped in every way, even by thoughts and attitudes
The manacles show how the poor were chained to the bottom also by crippling debt which meant that the poor stayed poor and couldn't move up the social hierarchy.
Might be a reference to the FrenchRevolution sounds like he thinks ordinary people suffer while those in the Palace are protected behind walls.
Those who were oppressed under the monarchy and powerful financial interests shed blood. Examples of those harmed and killed by the government are mentioned in the previous three lines