What does a position entail?

I am big fan of thinking through an argument from start to finish as well as assessing the implications of the argument.  Matt Yglesias did a good job with this approach with this post:

After all, the assumption that economic growth will continue undergirds conventional wisdom about economic policy in a really profound way—namely it's the key reason to limit political interest in redistribution of economic resources. There are a lot of metaphors about rising tides lifting all boats and baking a bigger pie instead of arguing about how to divide up a small one, and they're all pointing to the same issue—distributional issues matter, but in the long-term, economic growth matters much much more. Average living standards in the West are much higher in 2013 than they were in 1863 not because we abandoned capitalism and workers seized control of the factories, but because society as a whole is much more prosperous than it was 150 years ago.

It is an absolutely correct argument -- if there is no longer any potential for growth than pro-growth wealth distributions are kind of pointless and it becomes cruel to allow for high concentrations of wealth.  Now it is a different argument to claim that wealth concentration is required to encourage growth, but then the absence of growth should be a huge problem for low-tax/high-growth crowd.  Appeals to the long run get less compelling when the long run never actually arrives . . .