Marbury v Madison undermined the Oath of office

This is eagerness and readiness to fight comes from a certain understanding of the oath. The reason for the constitution mandating each office holder take and oath was to bind these individuals to commit to fight when they saw (on their own authority) that constitution needed defending. The oath lost that power to compel a fight despite the odds of failure. Culturally, we lost this sense of long-term honor to a name or reputation. But also, within Congress and the Presidency, the office holders lost the sense of authority for deciding what is constitutional and what is worth fighting for.