Kirsten Davies, the Department of War’s chief information officer and a 2026 Wash100 awardee, has announced the appointment of Ryan McArthur, former chief technology officer for public sector at Zscaler, as special adviser to the CIO for capability development and operational excellence as part of a broader set of appointments within the CIO office.

Davies is set to deliver a keynote speech at the 2026 Digital Transformation Summit. Sign up now for the April 22 event to hear experts discuss how data, AI and enterprise IT initiatives are transforming government operations.
In this role, McArthur will provide counsel on emerging technologies and support efforts to advance complex cyber and IT initiatives across the department’s portfolio. He will also help guide modernization efforts aligned with the “Arsenal of Freedom” initiative of Secretary of War Pete Hegseth, a 2026 Wash100 Award recipient, the Office of the DOW CIO said in a LinkedIn post over the weekend.
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Who Is Ryan McArthur?
McArthur most recently served as federal CTO at Zscaler, where he focused on advancing zero trust and cloud security capabilities across defense, intelligence and federal civilian agencies.
His government experience includes work with the Department of War and the Defense Information Systems Agency, where he oversaw the $9 billion Joint Warfighting Cloud Capability effort. He also served as a technical adviser to the DOW CIO and the U.S. Marine Corps.
McArthur is a retired U.S. Army signal chief warrant officer and an Operation Enduring Freedom veteran.
In a statement published on LinkedIn, McArthur said he valued his time at Zscaler, highlighting collaboration across government, industry and mission partners. He also expressed appreciation for the partnerships developed during his tenure.
Who Else Joined the DOW CIO Office?
Davies also announced the appointment of several additional leaders to key roles within the CIO office.
- Kayla Huthoefer Nelson, Chief of Staff. In this role, Huthoefer will support executive decision-making, organizational coordination and leadership priorities across the department’s IT, technology and digital modernization enterprise, including oversight of OCIO operations and strategy. She brings experience spanning government, the defense industrial base and venture-backed defense technology.
- Marci McCarthy, Director of External Engagements. In this capacity, McCarthy will lead strategic communications and engagement with industry, international allies and partners to support innovation efforts tied to the Arsenal of Freedom. She previously served as director of public affairs at the Cybersecurity and Infrastructure Security Agency, where she led media strategy as a presidential appointee and agency spokesperson.
- David Vaughn, Technical Adviser for Data Infrastructure. In this role, Vaughn will provide expertise on data and artificial intelligence infrastructure initiatives. He previously held roles across cyber operations, intelligence and enterprise risk management during a nearly three-decade career, including service as a U.S. Army chief warrant officer 4.
- Vishal Aswani, Special Adviser for Transformation. In this capacity, Aswani will support organizational change and business process reengineering efforts to improve agility within OCIO. He most recently served as chief of staff to the DOW CIO.
