The issue of min wage came up here before - the studies I found were mainly inconclusive, it's a hard one to test. One that came up, was a test in the food service industry (low waged) either side of a state border, one side with min wage the other without. It showed that the min wage tended to increased employment and improve the financial position for those employed with minimum wage vs. those in a non-min wage position. Indeed a larger increase in the in wage over the surrounding areas led to higher employment still.

I'll see if I can dig out that study later.

I can respect that it's difficult to isolate for the variables and testing the effects of minimum wage (ie you would have to isolate the "value" created from the various businesses like the food service companies), but the laws of supply and demand are pretty straightforward. Price floors (e.g. minimum wage) result in surpluses, price ceilings (e.g. rent control) result in shortages.

From an employer's perspective it's easy to see that the more you pay the more interest you'll get from those who can perform work better. The idea that employers would naturally exploit their workers is a bit silly given the ability for those workers to look elsewhere. And they do - which is why real wages have risen substantially over time (capturing some of the value in productivity improvements) to the point that in many cases entry level/effective minimum wages greatly exceed legislated minimum wage. The idea however that government should impose a choice means higher costs on society - in this case borne by the lowest wage earners as they are the ones who are least employable for whatever reason (by definition), means that fewer get hired.

And thus you get examples like this: http://www.seattlepi.com/opinion/153901_unemploy26.html

Well, this ought to be obvious. A trade union exists to promote the interests of its members and its leaders (not necessarily in that order). As the union itself creates no added value, it can only do this in a zero sum fashion - at the expense of both employers and the unemployed and anyone else who isn't a member.