You’re getting somewhere. If you take the same philosophy and rather than apply it to the political state, apply it to the economic state of capitalism. The implicit ‘agreement’ of buying goods (especially food) without the option of having land or wherewithal to grow one’s own food. This should apply to the level of the minimum wage: if one gives up their ability to provide their own sustenance, then wages paid should at least be equal to those resources and time.
To balance the quid-pro-quo with externalized costs in the capitalist system, all taxes should be at the decision point so that a citizen knows the consequences of their purchases in total. Government would then be sized according to informed citizen choices/demands for resources rather than deceived citizen choices being used as implied reasons to go to war over trade (especially oil).
We don’t usually need government services so much because we own land or property: we need government to step in when we make purchases beyond what is already owned, or when other citizens are deprived by deceptive practices and systems that favor keeping poor people (barely) alive with cheap products.
Justification comes along when citizens are informed and useful to their future resources (caring for the land and each other), rather than competing over wages for doing jobs that destroy the land and social resources.
Future usefulness becomes the justification rather than imaginary beings, with social justice (government) budgeted directly from consumption.