Politics, economics, demographics all come into play.
Residents suspect the involvement of widely resented security forces. But protests may not derail the relative peace of recent years.
As race for presidency nears, a new role is eyed for a former US ambassador Zalmay Khalilzad: Help Kabul work with the outside world.
If US president is too supportive of protests, he turns them into a 'Western plot,' say analysts.
Protesters reported beatings and shootings near the parliament Wednesday. Regime opponents vowed to persist with protests that have deepened a cultural divide between hard-liners and more moderate reformers.
The fatal shooting of a young man on a crowded downtown street illustrates why Americans could have trouble completely leaving this troubled provincial capital.