I think it will be a bit different. The mob will move out of the urban center to attack a suburb (as burning urban centers will eventually be recognized as stupid and futile). If the police withdrawal, suburban Americans will unload on the mob. The police will then reappear to protect the mob.
“The mob will move out of the urban center to attack a suburb...”
Black mobs won’t get past the Mexican neighborhoods without suffering serious casualties. Blacks and Mexicans are already at war in across America. The propaganda press has embargoed these stories from mass distribution. Here’s a sampling:
Attack on family in Compton latest incident in wave of anti-black violence
:
http://articles.latimes.com/2013/jan/25/local/la-me-0126-compton-20130126
Attacks on Mexicans Leave Neighborhood in Turmoil
http://www.nytimes.com/2010/07/31/nyregion/31staten.html?_r=0
Latino Gang Members in Southern California are Terrorizing and Killing Blacks
http://www.splcenter.org/get-informed/intelligence-report/browse-all-issues/2006/winter/la-blackout
The Problem With Race Wars Among Minorities
http://takimag.com/article/the_problem_with_race_wars_among_minorities_jim_goad/print#axzz3YugH16D1