There isn't a reason to lower it. But in some circumstances abolishing useless laws helps with bureaucratic costs and burdens on both the states and cities as well as business owners. If these costs exceeds the cost to abolish the law, then it might be worth it.

In my city, Pittsburgh, the minimum wage is $7.25 (the federal minimum.) I was looking for a part-time job over the summer. Every place had $8-$9 as their minimum wages. Walmart - $9, McDonald's - $8.5, Ikea - $9 (which is where I worked.) The only jobs I was looking at that were minimum wage jobs were the desk jobs at my university. And that is mostly because all you do is sit there most of the day on the computer, and they can't justify paying you more than minimum wage for that.

1. Where did the $3/h come from? The equilibrium wage would most certainly be greater than $3/h due to labor shortages at that price. In most areas, the lowest wages exceed our current minimum wage by $3-4 dollars. Nobody is going to work anywhere where they can't survive on the money they earn. That just isn't going to happen.

2. Europe has costs of living twice to quadruple the costs of living in the areas that have wages around the federal minimum wage here. Let's use my local scenario again. Somebody here who works 30 hours  - part-time - a week for $7.25/hr , gets $217.5 / week before taxes, and ~ $180 after taxes, per week (the taxes will return to them at the end of the year in a lump sum by the way.) They also will likely qualify for $150 in SNAP (food stamps) per month, if they live alone. My monthly food bill, and I don't eat poorly, is $120 - $140, so if I were on food stamps that would cover my food expenses. My monthly rent is $325 /month + $50 utilities for a one bedroom apartment. My monthly cell phone + internet bill is $70 /month. I don't have a car, but if I did lets say that is another $200 for gas + insurance (which is at the high-end) or I could take the bus for $1000/year. Health-insurance is free through medicaid for people who make minimum wage. If I made minimum wage, I would be able to survive on that $720 /month for only working 30 hours a week, and still have almost $70 left to spend on whatever I want or save that money. Sorry I don't see how having a $20/hr minimum wage would make one's quality of life any better in this context. What would happen is the minimum wage worker wouldn't have a job at all, and would be screwed. There are plenty of college graduates (who are unemployed and would be more reliable) or automated machines who can take those jobs at McDonald's for $20/h  or $0/hr + initial cost respectively. 

3. Minimum wage jobs are meant to be temporary jobs to gain experience. They are designed for students and entry-level employees. They are enough to survive and take care of oneself before one enters their real career, which one gains through self-improvement and learning useful skills. Any job that is designed to be a career tends to pay quite a bit above minimum wage.

Edit: I agree, even unskilled workers deserve their right to find suitable employment to take care of themselves. That is why I oppose minimum wages that exceed the equillibrium wage of an area (in other words: price-floors.)

There's a great article about him in the NY Times.
http://www.nytimes.com/2015/10/04/magazine/donald-trump-is-not-going-anywhere.html

$7.25 in US, €8.50 "brutto" (before taxes + social security contributions) in Germany.

That bitch won't make nomination. I'll mark this under classic Spurge joke, which in this case is not funny.

That is exactly what corporations want you to think. The fewer people who vote, the better it is for them and their candidates.

Though I don't think he can win, as others have said you should take a look at Bernie Sanders. He is the very antithesis of the "corporate politician". Someone like Bernie Sanders can only win if the people who want him to win go out and vote for him in the primaries next year.

Voting for Trump as sort of an experiment to see what happens is an interesting thought experiment, but not something to seriously consider imho.
Well not unless you're part of the top 1% and can afford having a laugh about a guy like that at the rudder of one of the most influential countries in the world.

I'm not American, but I would never vote for Trump! Not even if he would offer me 1 million dollars and a girlfriend!

Right... but when THEY are the ones who decide the options, it's a lose lose. Vote right? You lose. Vote left? You lose again.

Good luck with the next Kim Jong Un here from UK.

I'm seeing a lot of numbers thrown around here about European minimum wages that are completely false.
In my country, it's less than 70 euro a day, which is about 8.7 euro an hour, which is about 9.75 usd. This is The Netherlands, which is relatively wealthy and the wages are relatively quite equalized here.
In a country like Poland it's more like 3 usd an hour (even less).

I think a country like the US should be able to do better than both of these countries. Less inequality means less crime, happier people, more productivity. The US should be able to have drastically lower tuition fees so that everyone has a chance to be as productive as they can be.