Why is Georgia Avenue and Forest Glen Road different? Because it is a perfect storm of car traffic and pedestrian traffic. Note all of the things happening in close proximity:

• a major state highway with 8 lanes of traffic
• a major county road with 3-4 lanes of merging traffic
  
• a metro stop with an exit on only one side of a busy road (which results in higher than average pedestrian traffic)
• extremely close proximity to on and off ramps to the Capitol Beltway (which increases the speed of vehicles coming off a high speed interstate)
• limited visibility due to the underpass just south of the intersection
• high pedestrian usage by pregnant women and sick people (because of Holy Cross Hospital)
• high traffic attempting to reach Holy Cross hospital
• an intersection over capacity

When you start to examine all these factors, in one place, it's hard to justify the status quo.