Yes, climate change is a big issue, but it is not the biggest threat to national security. Democrats need to stop thinking that climate change is the super biggest threat to national security in the 21st Century. Sen. Kamala Harris (D-Calif.)'s question to Mike Pompeo today about climate change as a super issue looks tone-deaf. The biggest threat is terrorism, and intelligence.
Terrorism is not a big threat to the U.S. Even in their most successful year, 2001, terrorists haven't killed even as many as a third of what we do to ourselves each year with drunk driving. Except for that one bad year, we typically will see a hundred times more Americans die from domestic violence as opposed to terrorism.
Terrorism is flashy and gets attention, but as long as we exercise some reasonable prudence and precaution, it isn't a big threat, it's a little threat, at least to us. Now for those in the front-line areas of terrorism, it is a big threat, but that's the sort of internationalist reasoning that you're rejecting with respect to climate change. Global warming isn't a big threat to the U.S. because we have the wealth and other resources to be able to respond to its impacts, but that's not the case in much of the world. That is what makes climate change the next big thing likely to destabilize the world, often in countries already destabilized by terrorism.