There are very few “obvious” Americans in the list. One explanation is that we already have suitable tax sheltering/money hiding methods set up in the States. (Esp. in Nevada and Delaware.)
With so few Americans, there isn’t the shocking list of names that pop up for other countries. Iceland has already gotten rid of their PM via massive demonstrations. If Obama was on the list, there’d already been a House Impeachment Committee up and running.
Note: The law firm is Panamanian, the shell companies are set up elsewhere. Doing things thru Panama just adds another layer of opacity to the process.
(BTW: I keep thinking this story is about another topic when I read “Panama papers”.)