There are very good reasons for a progressive tax system.
#1. I don't believe your base ideas at all. Statistics show that majority of the rich work for it. Sure some inherit a bit of seed money but most by the third generation that money is gone. If I have any left I want some going to my kids regardless of what they have done or haven't done. It's my money, not some bureaurocrats that is telling me what to do, that is soaking everyone, that has a great retirement NOT tied to social security that guarantees them millions and their spouse the same. I am ready to start ranting if you can't tell.
#2. This is baloney. If you equally distribute all the money at one time so everyone is equally "rich" in a short time something like 5 years the distirbution would be like it is now economists say (conservative ones anyway). The rich work for it, desire things, are motivated, work to educate themselves and stay ahead and updated. Most people are not motivated by the same things or to the same degree, are happy with less, don't want to work that hard, do not have goals for attainment. Guess what, most of the philantrophic donations for research, for charity, for university football teams, for people in this country and over the world come from wealthier people. To equally share all the money-- it is not American. All wealthy people do not give money away which is their perogative since it is their money. Many, however, do great things. Poor people cannot give money to help poor people and they cannot buy food for other poor people if they cannot feed themselves.
#3. MORAL grounds??/ gov't teaching morals?? That is an oxymoron. Again if gov't would get out of the way and just do what was originally purposed for it to do (i.e. to protect us), everyone would have a lot more money and more money would be available in the people's hands for donations to poor, needy, etc. I should not be angry at gov't for spending my and also your money sooooo wisely. I don't think makes any difference to the party in power. With that much money around and available to the gov't, there is too much corruption and wasted money. I would rather give it all to my church (my example and doesn't have to be yours certainly) for a variety of missions that would more than take care of many causes that you mentioned in your original post.
I think we are looking for the same results just doing it differently.