He is not alone in his departure. A host of top officials are out as 2019 begins. Attorney General Jeff Sessions pushed out, John Kelly eased out and Nikki Haley resigns on good terms. It’s assumed Kirstjen Nielsen will be eased out soon.
Mattis “retired” according to President Trump. In fact, his resignation letter made clear he quit over major policy disagreements with the President and his national security team. The letter never praised nor thanked Trump, but highlighted specific criticism for Trump’s alliance policy, especially with NATO, and his approach toward “malign actors and strategic competitors.”
The key paragraph:
Because you have the right to have a Secretary of Defense whose views are better aligned with yours on these and other subjects, I believe it is right for me to step down from my position.
Mattis, as opposed to most senior officials departing the Trump administration, was ahead of the President’s tweet and framed the issue to his specification. Some language follows:
One core belief I have always held is that our strength as a nation is inextricably linked to the strength of our unique and comprehensive system of alliances and partnerships. While the US remains the indispensable nation in the free world, we cannot protect our interests or serve that role effectively without maintaining strong alliances and showing respect to those allies.
…we must use all tools of American power to provide for the common defense, including providing effective leadership to our alliances. NATO's 29 democracies demonstrated that strength in their commitment to fighting alongside us following the 9-11 attack on America. The Defeat-ISIS coalition of 74 nations is further proof.
China and Russia:
Similarly, I believe we must be resolute and unambiguous in our approach to those countries whose strategic interests are increasingly in tension with ours. It is clear that China and Russia, for example, want to shape a world consistent with their authoritarian model - gaining veto authority over other nations' economic, diplomatic, and security decisions - to promote their own interests at the expense of their neighbors, America and our allies. That is why we must use all the tools of American power to provide for the common defense.
Respect for Allies, Clear-eyed About Adversaries:
My views on treating allies with respect and also being clear-eyed about both malign actors and strategic competitors are strongly held and informed by over four decades of immersion in these issues. We must do everything possible to advance an international order that is most conducive to our security, prosperity and values, and we are strengthened in this effort by the solidarity of our alliances.
Read full resignation letter here