In the years since 9/11, corporations have been doubling down on their own disaster recovery capabilities. Internal cloud architectures, as well as the ability to run multiple live data centers with active failover, have decreased the time between system failures and data recovery points. The single biggest change to emerge in the post-9/11 world has been a new focus on keeping workers working when corporate systems go down. Public services and corporate disaster recovery teams have stepped up their use of social media, such as Facebook and Twitter.”]
Source: https://www.csoonline.com/article/2129541/9-11–top-lessons-learned-for-disaster-recovery.html