Taking my property to fund your moral imperative is not charity - and not moral

Redistribution of wealth - taxation to pay for universal health insurance, for food stamps, for welfare payments, and all other gems of the liberal mind - is simply the forceful theft of property.  Self-titled "progressives" often argue that such theft must be moral because all the civilized world does so.
Consider slavery. Slavery was a common, almost global practice a few hundred years ago. That didn't make it right.

Or consider women's suffrage. I don't know of any country which allowed women to vote in the 19th century. That didn't make it right.

The majority of the U.S. population currently believes it is acceptable to force productive citizens - and only productive citizens - to be charitable. That doesn't make it right.

Libertarians and like-minded citizens are trying to change this nation, just as abolitionists changed the nation in the 19th century and suffragists did in the early 20th century.

Charity - voluntary transfer of property to someone you deem unfortunate - is admirable and has existed for denturies if not millenia.  But what moral argument can support the belief of "progressives" that it is acceptable to force some of the population to be charitable?