Special anti-terror police forces were deployed on UK streets as of Monday ready for chaos in event of the Theresa May cabinet falling over the Brexit document she negotiated with the EU, and terrorists taking advantage of the pre-Christmas shopping season. May’s fight to save her cabinet from a parliamentary majority ranged against it, including rebels from her own Conservative party, reaches its decisive moment this week. Britain’s exit from the EU without a negotiated deal would lead to chaos in the flow of imported essentials to the UK, its exports, industries and the financial sector. Shortages could provoke street disturbances in the big cities in the middle of the largest shopping event of the year. The big department stores in London and major cities have given sales staff special instruction for their conduct if faced with terror attacks or crowd disturbances.