Consumer spending does affect the economy in the short run, but long-run economic growth is associated more with investment in capital goods than it is with consumer spending. (Although there are a lot of interaction and feedback effects in these relationships which aren't really worth going into right now.) [I will readily admit, though, that fluctuations in consumer spending can definitely affect the economy in the short-run.]
Not sure I understand this. Capital goods, IIRC, are machines, factories, etc. - the stuff we use to make consumer goods. So, I'm curious how consumer spending does not support the long run as much as capital goods?