Private surplus in the last chart just means corporate surplus, I'm not sure why you use the word "we" there. "We" are represented by the gov't line since our tax dollars are what finance the gov't- at least initially (maybe just theoretically -eye roll), until our taxes aren't enough and the gov't relies on issuing bonds to raise the rest of the cash it needs.

I used to think the debt did not matter either but i have changed my mind. It takes something like $5 dollars of borrowed money to raise our GDP by $1. And interest payments on the debt is so large that the only we have been able to pay it is it "issue" more money, watering down our currency to make payments. Somewhere along the line printing money to make payments on old borrowed sums stops making sense, like making mortgage payments on a house after its value got cut in half, you are underwater and bailing with a bucket stops helping.

so the debt is important