I think one of the problems from "being indispensable" is the direction it takes. Being indispensable in regards to people "being left holding the bag while new

I think one of the problems from "being indispensable" is the direction it takes. Being indispensable in regards to people "being left holding the bag while new initiatives are undertaken" means they are/were indispensable in regards to specific tasks/processes/skills or knowledge. Personally I feel being indispensable can also be seen as being able to be thrown at (nearly) any problem and finding a solution. Catching the ball and creating the basis for a stable project for others to take over/maintain. I am working at an agency and more often than not there is a first small initiative at a client where we just do not know what is expected/needed in terms of skills and in what direction this initiative might go/grow. So we often throw two people at the "problem". One more senior "jack of all trades" kind of person that can understand a lot of problems and knows how far they themselves can work towards a solution (and when to call in the subject matter experts). And one more junior person to support and learn by swimming in cold water together with said "senior" (can actually - depending on the problem be a junior/intermediate themselves - it depends). These "jack of all trades" persons, thinking on their feet, being able to improvise and get things done, able to understand and dig into problems ans find solutions - these kinds of persons are indispensable - but they don't get stuck in one specific problem/project. The processes around them are built in a way so that we free them for the next thing to come our way. And we do everything we can to create new people of that kind. I'm not really familiar with the military context, but it's almost how I envision an advance/special forces unit operating in front of the actual lines and first creating a beachhead that the regular troops can then build on and bring their strengths to bear. These types of individuals are indispensable - but ideally not each of the individuals on their own.