“Knavery seems to be so much the striking feature of its [America's] inhabitants that it may not in the end be an evil that they will become aliens to the kingdom.”

I think he's jealous

i think that he is saying that the colonies might help them

A knave and blackguard should know.

Ask Dr. Joseph Warren et al.

Knavery?  Is liberty knavery? I think not. Is it knavery to be a patron of evil (tyranny, despotism, social slavery, a patron of the occupying statist theocracy now infesting this land)? — YES ! ! ! absolutely, I think so.

" Come out from among them and be ye separate " was/is the furthering of a gracious movement on behalf of the Creator's mercy. Now as allies, the Patriots of Liberty within the UK, who lost and seek to regain their Independence. Their Patriotic knaves revolt against the tyranny in their own ranks of government.  

Damage control.  Sycophants agree.  We see the same thing today every time some nation tries to exercise their sovereignty against the will of a council that lays claim to regulate them.

Ahoy mates! Be we just knaves of the liberty minded sort? Indeed suh! But then we now have a "government" intent upon destroying our hard fought "knaveness"...mayhaps it's time to take up arms and toss the tea into the harbor!! Along with those self proclaimed Kings!!
I, sirs, am justly proud of my knaveness!!