New Delhi, Aug. 1 -- HARARE - Armed police units arrived in Harare's central business district before sunrise on Thursday, taking up positions across the city's main arteries hours before the first protester was expected to appear. By midday, the city was quiet. Not the quiet that comes after something ends, but the kind that signals nothing will begin.

The July 31 demonstrations, called by opposition groups and civil society activists to challenge Constitutional Amendment Act No. 3, collapsed before they could form. Zimbabwe Republic Police confirmed in a statement that officers had been deployed "in all parts of the country for effective maintenance of law and order." Police Commissioner Paul Nyathi, announcing the measure on Tuesday, ...