The Budget Game

I'm trying to refine my ideas about how the two party political system in the U.S. works.  One idea that I have read about is that the outcome of a game will depend on the power of the players, the strength of their positions and the importance that they place on the conflict.  I want to apply this to conflicts over the budget at the federal level.

As I have indicated in previous posts the Republicans value low taxes, high military spending and low social spending in descending order of importance.  The Democrats value high social spending, high taxes and low military spending, likewise in descending order of importance.  However, I'm much less sure on this one.  Perhaps I have the last two priorities reversed.  Maybe their interest in these two is roughly equal.

We could estimate that the Democrats are four times as interested in social spending as they are in each of the other two.  At first I considered that they might be three times as interested, but then I dismissed this because it seemed to under-estimate the extent to which the Democrats value social programs.  If this were the case they would value cuts in military spending coupled with tax increases two-thirds as much as increases in social spending.  That seemed insufficient to me.  If we are dividing up 100 points we would give 67 to social programs and 6.5 to each of the other two.

Similarly I would estimate that the Republicans value lower taxes twice as much as military spending, which they value twice as much as lower social spending.  That would be 57 for low taxes, 29 for military spending and 14 for low social spending.

In the absence of action, mandatory spending will continue and discretionary spending will stop.  It follows that mandatory spending should continue, and discretionary spending should depend on the strength of the two parties.

I suspect there is something wrong with the model.  Historically the two parties have been roughly equal in strength.  How do we explain why most of the discretionary spending is on defense?  Perhaps the Democrats are paying for permanent enactment of mandatory social programs in return for spending on national defense.  This seems rather short sighted on the Republicans part.  Perhaps the Democrats are more risk averse when it comes to social spending than the Republicans are on military spending.

To be sure it isn't out of character for politicians to be short sighted, but why wouldn't the Democrats take advantage of the situation in order to get even more social spending?  Unless I am wrong about the values of the two parties, the democrats should be able to get more in discretionary programs than the Republicans get for defense.  In addition to paying for increases in defense, the Republicans will need to pay for tax cuts.