A look at the rise and fall of IronNet, a cybersecurity firm led by ex-NSA director Keith Alexander and whose valuation crossed $3B after it went public in 2021 (Alan Suderman/Associated Press)

Alan Suderman / Associated Press:
A look at the rise and fall of IronNet, a cybersecurity firm led by ex-NSA director Keith Alexander and whose valuation crossed $3B after it went public in 2021  —  The future was once dazzling for IronNet.  Founded by a former director of the National Security Agency and stacked …