Office building security changed significantly much earlier than 2001. The mass shooting in 1993 at 101 California Street in San Francisco was the beginning of many such changes.
The attack [...] also precipitated sweeping changes in downtown San Francisco. Before Ferri walked into the building that July day, almost no high-rises in the city had security measures. While many had a front desk, only a handful checked badges. The building at 101 California had two side entrances that were completely unguarded. The Examiner reported that at the time, the Chevron building and Charles Schwab’s SF headquarters had the toughest security in town; electronic badges were required at Chevron, an anomaly in 1993.
Today, security checks are standard at offices large and small, a fundamental shift that happened because of 101 California.
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