Offer your thoughts or opinion on the input financial query or topic using your financial background.

Why is economic growth so important? 
One of the best answers to this question that I've ever read is in a paper published by Robert Lucas in the Journal of Economic Perspectives. That journal is meant to a be a place for experts to write about their area of expertise (in economics) for a general but still technically-minded audience. They recently opened up the journal as free to the public, which is a fantastic resource -- you no longer need a subscription to JSTOR (or whatever) to read it.  You can read the abstract to the paper, and find a link to it, here. One of the things that I like a lot about this paper is that it strips out absolutely everything even slightly unnecessary to thinking about a macroeconomy, and just discusses what one can arrive at with a very very simple model. Of course, with great simplicity come sacrifice about details. However, it does a great job of answering your question, "why do people care about growth?" A quick note: the key to understanding the answer to your question is to think about things in terms of "the long term"  -- not even looking forward to the future, because we'll be dead by then, but looking back to the past. The key to the importance of growth is that, for the last ~200 years, the US has, on average, had maybe 2-3% "real growth" per year (I'm pulling these numbers out of my head; I think much better numbers are in that paper somewhere). On average, over that period of time, this growth has meant that the quality of life that one has, if one lives in a country experiencing this growth, is enormous compared to countries that do not experience this average growth over that period.  Statistically speaking, growth is also somewhat auto-correlated. Roughly speaking, if it was low the last few periods, you can expect it to be low the next period. Same thing if it's high.   Then, the reason we care about growth right now: if you have too many periods of low growth, pretty soon the average "over the long term" growth will be pulled down -- and then quality of life can't be higher in the future (which quickly becomes someone's "present"). The paper above makes this point with a very simple model. Of course, none of this touches on distributional issues, which are another issue entirely. With respect to, "The economy needs to grow to just keep up with its debt repayments," I think the answer is along the lines of, "sometimes countries get into debt expecting that growth will increase their resources in the future, and thus they can pay back their debt." That strategy is, of course, the strategy that anyone borrowing ("taking out a loan") should be employing -- you should expect that your future income will be enough to pay back your interest+principle on a loan you took. Otherwise you're irresponsible. At the aggregate level, production is the nation's "income" -- it is what you have, all that you have (as a nation) to pay back any debt you've incurred at the national level.