Constraints on Presidential War Power
Matt Glassman:
My view, as discussed last week, is that presidential warmaking is an almost wholly political issue, rather than a legal one. No court is going to stop a war.
That said, I think may people hear "wholly political" and just assume that the president has a free hand to do whatever he/she wants. I completely disagree. In fact, presidents are incredibly constrained by politics when it comes to war.
Take Trump and Iran. What are some of the major political constraints:
- Military capacity
- Cooperation of allies
- Reaction of foreign adversaries
- Reaction of markets
- Congressional opinion
- American public opinion
- Partisan/base opinion
The first two---military capacity and ally cooperation---are straightforward; they are essentially supply-side constraints. Presidents can only go to war with the military Congress provides. Ditto with allies; absent the ability to use airspace and foreign bases, some operations become impossible. And it's always better to have a coalition of nations fighting the war than going it alone.
The third and fourth items on the list---foreign and market reactions---are constraints because they create immediate negative feedback, political and economic. Trump can't just nuke Tehran because that could easily trigger an escalation to global war, and WW3 with China is a bad outcome. Similarly, now that Iran has closed the strait and oil prices are spiking, the economic costs of the war may soon exceed the benefits, encouraging the president to seek a diplomatic off-ramp.
The final three items---opinions in Congress, the public, and the president's party---are the most purely political. These matter because the president has goals other than the objectives of the war, and negative opinions about the war will inevitably spill over to future political goals, whether they are policy, electoral, or egoist.
