Actions that you take legally must have consequences too, as long as these consequences are legal the thread of legality has been preserved along the way. It's not a punishment, it's a consequence. I am not born in the US, thus I don't have the right to be the US President, is it a punishment ? No it's simply a consequence.
I would love all people that say that we need to "fix" the tax system instead of making "rich go" to take a step back and get out of their simplistic views. The tax system and a state is infinitely more complex than any company you could imagine. The worst part is that a country sets its own rule and thus has way more responsibility. Moreover higher instances require a state to behave a certain way and prevent certain behaviors. Even worse, external entities such as foreign countries can interfere with internal regulation mechanism (that's what's happening in this case).
The US being a relatively free state cannot prevent any body to abandon a nationality and thus to lower their tax. For most it's an important procedure which allows you to forfeit other nationalities and take a nationality that requires you to have no other nationalities( some countries impose that). Tax evasion is a constant battle because the laws have to guarantee cases like the one I mentioned but they are also used to save money. Thus legislator are constantly fighting a war against tax evasion and this is one example.
Again, your success has a burden on the whole community and we have to pay it. I know why it's so hard to understand here, many of you who see themselves as future entrepreneurs are thinking "Oh gosh, it's going to happen to me one day, I don't like that" and want to fight against it, but really try to see vastness of the complexity of the problem. There is no simple fix.
edit: Changed the phrasing