The role of the Secretary of Defense is a critical position in the United States government, responsible for the formulation and implementation of national security and defense policies. During the presidency of Donald Trump, there were two Secretaries of Defense who played significant roles in shaping the country's defense strategy and policies. The first was James Mattis, a retired Marine Corps general, who served from January 2017 to January 2019. Mattis brought a wealth of military experience to the position, having commanded troops in Iraq and Afghanistan, and was known for his strategic thinking and strong leadership skills.
James Mattis: The First Secretary of Defense Under Trump

During his tenure, Mattis focused on strengthening the US military’s readiness and capabilities, while also emphasizing the importance of alliances and partnerships with other nations. He was a strong advocate for the US to maintain a strong military presence in key regions, such as the Middle East and Asia, to counter emerging threats from countries like China, Russia, and Iran. Mattis also played a key role in the development of the National Defense Strategy, which outlined the US military’s priorities and goals for the next several years.
Key Initiatives and Policies Under Mattis
Some of the key initiatives and policies implemented during Mattis’ tenure included the expansion of the US military’s presence in Afghanistan, the strengthening of alliances with NATO and other European partners, and the development of a new nuclear posture review. Mattis also emphasized the importance of investing in emerging technologies, such as artificial intelligence and cybersecurity, to stay ahead of potential adversaries. However, his tenure was not without controversy, as he faced criticism from some lawmakers and experts over the US military’s role in various conflicts, including the war in Yemen.
Secretary of Defense | Tenure | Key Initiatives |
---|---|---|
James Mattis | January 2017 - January 2019 | National Defense Strategy, Expansion of US military presence in Afghanistan, Strengthening of NATO alliances |
Mark Esper | July 2019 - November 2020 | Implementation of National Defense Strategy, Focus on emerging technologies, Strengthening of alliances with Indo-Pacific partners |

Mark Esper: The Second Secretary of Defense Under Trump

Mark Esper, a former Army secretary and defense industry executive, succeeded Mattis as Secretary of Defense in July 2019. Esper’s tenure was marked by a focus on implementing the National Defense Strategy, which emphasized the need for the US military to adapt to emerging threats from countries like China and Russia. He also prioritized investing in emerging technologies, such as hypersonic missiles and advanced cybersecurity capabilities, to stay ahead of potential adversaries.
Key Initiatives and Policies Under Esper
Some of the key initiatives and policies implemented during Esper’s tenure included the development of a new defense budget that prioritized investment in emerging technologies, the expansion of the US military’s presence in the Indo-Pacific region, and the strengthening of alliances with partners in the region. Esper also faced challenges, including the COVID-19 pandemic, which required the US military to adapt its operations and protocols to protect troops and maintain readiness.
Key Points
- James Mattis and Mark Esper served as Secretaries of Defense under President Trump, each bringing unique experiences and perspectives to the role.
- The National Defense Strategy, developed during Mattis' tenure, emphasized the need for the US military to adapt to emerging threats from countries like China and Russia.
- Esper prioritized investing in emerging technologies, such as hypersonic missiles and advanced cybersecurity capabilities, to stay ahead of potential adversaries.
- Both Mattis and Esper faced challenges, including controversy over the US military's role in various conflicts and the need to adapt to emerging threats and technologies.
- The role of the Secretary of Defense is critical in shaping the US military's strategy and policies, and requires a deep understanding of national security issues and the ability to work effectively with lawmakers, allies, and other stakeholders.
In conclusion, the Secretaries of Defense who served under President Trump, James Mattis and Mark Esper, played critical roles in shaping the US military's strategy and policies. Their tenures were marked by a focus on strengthening the US military's readiness and capabilities, while also emphasizing the importance of alliances and partnerships with other nations. As the US military continues to evolve and adapt to emerging threats and technologies, the role of the Secretary of Defense will remain critical in ensuring the nation's security and defense.
What were the key initiatives and policies implemented by James Mattis during his tenure as Secretary of Defense?
+During his tenure, Mattis focused on strengthening the US military’s readiness and capabilities, while also emphasizing the importance of alliances and partnerships with other nations. He was a strong advocate for the US to maintain a strong military presence in key regions, such as the Middle East and Asia, to counter emerging threats from countries like China, Russia, and Iran.
What were the key initiatives and policies implemented by Mark Esper during his tenure as Secretary of Defense?
+Esper prioritized investing in emerging technologies, such as hypersonic missiles and advanced cybersecurity capabilities, to stay ahead of potential adversaries. He also emphasized the importance of implementing the National Defense Strategy, which outlined the US military’s priorities and goals for the next several years.
What are the key challenges facing the US military in the future, and how can the Secretary of Defense address them?
+The US military faces a range of challenges, including emerging threats from countries like China and Russia, the need to adapt to emerging technologies, and the requirement to maintain readiness and capabilities in the face of budget constraints. The Secretary of Defense can address these challenges by prioritizing investment in emerging technologies, strengthening alliances and partnerships with other nations, and ensuring that the US military has the resources and capabilities needed to meet emerging threats.