These events do not arise in isolation but combine with existing social and political conditions and can disrupt societies and nations. They harm people directly or degrade the social, political, economic, agricultural, ecological or infrastructural systems that support them.

With these environmental changes we should expect disruptions to global water and food security, reduced economic security and weakened livelihoods, worsened human and animal health, and risks to the global supply chain on which the United States and its partners depend. Political instability, heightened tensions over resources, climate-linked humanitarian crises and adverse effects to militaries in some places are likely to increase. Migration will probably increase both within and between nations, with sociopolitical and resource implications already becoming clear.

Despite the increased politicization of climate change, I embraced the opportunity to participate in an unclassified congressional hearing on such an important matter. In particular, I welcomed the chance to engage Republican members of Congress on the topic because of the party’s historically strong support of other science and technology issues. Previous closed-door discussions persuaded me that at least some Republican lawmakers were open to the argument that climate change was a national security concern. I believe that once one accepts that global temperatures are increasing, a fact that only the most ardent climate disbeliever rejects, the case for that fact’s relevance to nation security directly follows.

When I joined the government in 2009, leadership was generally receptive to environmental security analysis. After the administration changed in 2017, my job was arguably even more important because of the skepticism within the Trump administrative over climate change. The intelligence community tries to deliver objective truth to decision makers — truth that persists irrespective of who occupies the White House.

I take great pride in the many positive and productive interactions I had with senior officials in my 30 months in the Trump administration. But the decision to block the written testimony is another example of a well-established pattern in the Trump administration of undercutting evidence that contradicts its policy positions.

Beyond obstructing science, this action also undermined the analytic independence of a major element of the intelligence community. When a White House can shape or suppress intelligence analysis that it deems out of line with its political messaging, then the intelligence community has no true analytic independence. I believe such acts weaken our nation .

My last day on the job was July 12. In the weeks since the hearing I came to understand that there was little left for me to achieve in my position. More than most officers in the intelligence community, I interacted often with the public in discussions of environmental security issues. After the experiences of the prior two months, I wondered whether I could continue public engagements without being tainted by questions about my own analytic independence.

Grappling with the implications of climate change and biodiversity loss, the two primary security concerns I’m focused on, is too important to me to wait around for a possible change on these issues in a future administration. We need to better understand and anticipate the challenges facing the nation and its partners. Whatever my next step might be, I believe these issues remain critical, and I will try to continue this work going forward.

Rod Schoonover was, until recently, a senior analyst in Bureau of Intelligence and Research at the State Department. He also worked as director of environment and natural resources at the National Intelligence Council and was a professor of chemistry and biochemistry at California Polytechnic State University, San Luis Obispo.

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