US Foreign Policy
The Use of Military Force
Michael E. Flynn
Kansas State University
Updated: 2021-09-13
Lecture Overview
What constitutes a "use of force"?
Trends in the use of force over time
When and why does the US use military force?
Limits on the use of force
Key Questions
What does US military activism look like over time?
What constraints do policymakers face when using military force?
Wha domestic factors shape incentives to use military force?
Why do policymakers escalate (or not) military conflicts?
What role do concepts like "resolve" play in the use of force?
What Constitutes Force?
Notes:
- Talk about generla misperceptions of what constitutes military force
- We typically think of big cases, but most are small.
- If it pops into your mind, it's probably a bad representative case.
What Constitutes Force?
What do we mean when we talk about the use of force?
This probably seems obvious, but reality differs from most people's perceptions
Most uses of military force are short duration and low intensity
Large-scale uses of force (i.e. wars) are relatively rare
Notes:
- Operation Overlord - The invasion of Normandy on D-Day in WWII.
- Massive multilateral military operation that took months of planning.
- This is a highly salient, but highly unusual example of military force embedded within an already enormous military operation.
Notes:
- US Navy and Marines conduct an operation to retake a ship from pirates in the Gulf of Aden
- This is not Captain Philips, but similar.
- Smaller operation, limited goals
Notes:
- USS Porter launches cruise missiles into Syria in response to reports that Syrian government used chemical weapons against civilians.
- Smaller operation, more limited goals.
- Intent is to signal more than achieve general military goals.
- We'll talk more about this point later
What Constitutes Force?
What do we mean when we talk about the use of force?
This probably seems obvious, but reality differs from most people's perceptions
Most uses of military force are short duration and low intensity
Large-scale uses of force (i.e. wars) are relatively rare
Notes:
- Militarized interstate disputes (MID) represents a way to conceptualize a broad range of cases where force is used
- Not all of these are purposeful policy actions
- Many represent impulsive acts on the part of agents in the field
Notes
- What are the patterns here?
Notes
- Broken down by type
- Notice that green and yellow are the most common categories
Notes
- US MIDs relative to all mids in a given year
- US Accounts for a fairly high proportion of total MIDs in any given year.
Notes:
- Notice that most conflicts are very short.
- Mean is less than 6 months,
- Median is only 0.04 years---only about 14 days.
- Side point---this is why stats is handy. Average isn't always the best indicator to use.
When and Why Does the US Use Force?
When and Why Does the US Use Force?
Motivations:
- Protest citizens abroad
- Acquire territory
- Secure commerce and access to markets
- Secure access to to resources
- Remove hostile leaders/governments from power
- Check expansion of rival powers
- Signal resolve
- Strikes against actors who use terror
- Intervene for humanitarian reasons
Notes
- Countries use force for all sorts of reasons
Notes:
- Occupation of Veracruz, Mexico in 1914.
- Began with the arrest of 9 US service personnel who went into a restricted part of the city. They were released a short while later.
- US Admiral Mayo demanded an apology (which he got) and a full 21 gun salute from the Mexican military.
- Victoriano Huerta had come to power in a coup during the Mexican Revolution. President Wilson hoped to push him out of power. Wilson decided to use this as an opportunity to increase pressure on Huerta and backed Admiral Mayo's demands. Huerta refused.
- Wilson asks Congress for approval to use military force against Mexico in response, and both the House and Senate vote to approve the use of force against Mexico.
- Approximately 6,500 Marines invade and occupy the city
- Shortly after military operatiosn begin Wilson gets word of a ship about to dock at Veracruz that contains machine guns and munitions, which he fears will strengthen Huerta's regime.
- Wilson thinks US troops will be greeted as liberators, but Mexican naval cadets and civilians start fighting US forces after Huerta's forces pull back. Huerta's opponents also denounce the US intervention, contrary to Wilson's beliefs (sound familiar?)
- Source: CFR Page on the invasion of Veracruz
When and Why Does the US Use Force?
But what general factors should we think about?
Two broad categories:
International factors
Domestic factors
When and Why Does the US Use Force?
International factors
Opportunities to use force
Interests
Security Interests
Economic interests
Notes
- Specific details vary, but we can distill motivations down into some broad groupings
- Security interests would be things like destroying a rival's capacity to launch an attack on the US, or thwarting an actual planned attack.
- Economist interests csan include access to new markets, or access to natural resources
| Predictor | Civil Wars | International Crises |
|---|---|---|
| Ally involvement | + | + |
| Rival intervenes first | + | + |
| Volume of trade | ||
| Relative power of target | ||
| Distance from US | + | |
| Population of target | - | |
| Democratic states | ||
| US growth rate | ||
| # Other states involved | - | |
| Note: | ||
| Fordham, Benjamin O. 2008. Power or Plenty? Economic interests, security concerns, and American intervention. International Studies Quarterly. 51(1):737-758. |
Notes:
- Fordham (2008) analyzes cases where the US intervenes in international and internal/civil conflicts
- Talk about coefficients
Notes
- Short run effect of trade on alliance formation
When and Why Does the US Use Force?
Resolve
- Politicians often talk about this a lot, but what is it?
A signal that an actor is willing to endure costs over a long period of time
- But how can actors effectively communicate resolve?
Notes
- Resolve is often something that politicians talk a lot about
- Cases like Trump's cruise missile attacks on Syria are intended to demonstrate US resolve and signal the US' seriousness about a particular policy issue
- Dr. Danielle Lupton has done work on this. She discusses the fact that things like cruise missile strikes are viewed as safe and effective means of signaling US intent and resolve, but the fact that they're low cost undermines their effectiveness.
Notes
- Mike Pence famously walked up on to the parapet and said he wanted North Koreans to see the resolve on his face
- Lupton's research suggests this kind of thing makes for a good photo op, but does little to actually communicate resolve or effectively signal intent to an adversary, particularly when earlier statements and actions undermine these later efforts.
- Lupton's research also shows that leaders who fail to live up to their hawkish rhetoric face consequences. She notes that this stuff might play well domestically, but have consequences internationally.
When and Why Does the US Use Force?
Domestic Political Factors
Diversionary use of force?
Partisanship?
Ideology?
Notes
- Various domestic factors can also matter
- But what are they?
- Do leaders use force to distract from domestic problems?
- Are the parties different?
- Does ideology shape incentives to use military force?
When and Why Does the US Use Force?
Diversionary Use of Force
The idea is to distract from poor economic or domestic political conditions
Use of force triggers a "rally" effect, increases presidential approval/favorability ratings
Notes:
- It can be REALLY hard to escape damning domestic political events
- Using military force typically doesn't create sustainable conditions that can help leaders distract from their problems.
When Does the US Use Force?
But diversion may be more complicated
Parties are better/worse equipped to respond to "bad" conditions
We can think of policy as substitutable, rather than strictly as diversionary
Example: Unemployment
Democrats
Republicans
Notes
- Diversion can be more complicated
- Parties don't face the same incentives, and don't have the same cost-benefit calculus when looking at different policy options.
- Democrats typically don't have the same limits as Republicans when it comes to inflationary macroeconomic policy. They can respond to growing unemployment with stimulus spending more easily.
When Does the US Use Force?
What about other countries?
So far we've assumed the US initiates the use of force, but sometimes it's also a target
We often focus on decision-making within the US, ignoring the decisions of other states
What sorts of factors determine when other countries target the US, and the intensity with which they do so?
When Does the US Use Force?
When is the US a target?
- A few factors to consider
- When is a target vulnerable?
- When is a target's hands tied?
- When do you want to avoid "poking the bear"?
Diversionary logic can help us here:
- Economic conditions: States try to avoid conflict with the US when economic conditions are bad (e.g. high unemployment).
- Partisanship: Prior beliefs about how likely presidents of different parties are to use military force may shape other states' decisions about attacking the US.
- Rivalry: States with long-standing grievances and hostility towards the US may be more likely to use force in general.
| Outcome/Variable | Effect |
|---|---|
| Conflict Intensity | |
| US conflict behavior | + |
| US Unemployment rate | - |
| Democratic president | + |
| Communist state | + |
| Variation in State Behavior | |
| State power | + |
| Communist regime | + |
| Note: | |
| Dave Clark, Ben Fordham, and Tim Nordstrom. 2011. Preying on the Misfortune of Others: When do states exploit their opponents' domestic troubles? Journal of Politics. 73(1):248-264. | |
Notes
- Focuses mostly on the Cold War period, so some of these effects may be more or less relevant today.
Limits on the Use of Force
Limits on the Use of Force
A puzzle:
The US is the most powerful state in history, but it loses wars and we never see its military capabilities used in full. Why?
What constraints exist on US military power?
What are the limits of US military power?
Limits on the Use of Force
Some key factors:
Risks, costs, benefits
Public support
What will allies do?
What will rivals do?
Is the military the appropriate instrument of power for the goal in question?
Limits on the Use of Force
Domestic public support
Public support generally diminishes over time
As a rule, the costs of war only grow over time
Military force becomes increasingly political, leading to greater congressional involvement
Conflict reveals information over time, and may reveal faulty assumptions from war's beginning
Limits on the Use of Force
What will allies do?
Allied leaders may press for limits on the scope of conflict
They might withold capabilities
They might limit mission types in which their troops can participate
Allied publics might not support expanding the scope of conflict
Limits on the Use of Force
What will rivals do?
Rivals might greet US escalation with their own action
Rivals may benefit from overly aggressive US action
Rivals might also ramp up their efforts to counter US in other geographic/issue areas
Limits on the Use of Force
Are there better options?
The US has come rely more and more on the military to do a wide range of tasks
But the military may not always be the best tool for the job
The use of force often requires deploying other forms of power, influence, and expertise, but the military can't generate comparable levels of expertise in all issue areas as compared to other agencies
Efforts to build soft power may be undercut or offset by US military presence