FWI/Thought experiment: The US is annexed by Canada.

I posted this comment and want to know if you think this would happen:

Which came first though? If the US were annexed by Germany or Canada tomorrow and all Americans had some income and health security, had sensible gun laws, and had peaceful police, gang membership and violence would plummet within hours, as would the constant fear of losing everything. Gangs reflect a failure of society to guarantee security.If you get rid of at will employment too, people will be less scared and les likely to turn to criminal syndicates.

Context: https://np.reddit.com/r/europe/comments/3gl0lp/earlier_this_summer_we_led_a_delegation_of_people/ctzo10d?context=3

What do you think would occur if the US was integrated into Canada tomorrow? Maybe not as plausible as some others, but can't think of a better place to discuss.