Pentagon fallen for the myth too?
"the Pentagon wasn't doing enough to keep up with evolving threats by, among other things, adopting the cutting-edge strategy of agile software development"
In my experience, 'agile' development (expressly in quotes as that reflects common practice*) contributes significantly to vulnerability to evolving threats. That's primarily due to the difficulty of integrating universally adhered-to coherent secure development practices into a coding environment that proceeds directly from concept to implementation at the discretion of multiple separate development individuals or teams, eliminating a centralised formal design stage.
Agile is an excellent approach for UI and non-critical functionality, but it's not a panacea. More rigorous methods are needed some cases, particularly that of sensitive data processing.
*What passes for 'agile' is in many cases merely uncontrolled and poorly documented ad hoc coding.
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