RummyBoy

The USA cannot hijack this bank in any way (its China's baby). However, having the USA on board is important because they will want the USA's vote on substantive issues to make the system work well.

China's Asia Infrastructure Investment Bank gambit has U.S. leaders on edge

From the above:

"Banking analyst Dick Bove has joined the chorus of those worried about what the rise of the AIIB might portend.

The vice president of equity research at Rafferty Capital Markets called it "a major defeat for the United States" that, save for Japan, "every other major ... ally from Britain to Israel to Australia has joined. These countries joined despite the expressed wish of the United States that they not do so."

Many analyses of the AIIB's rise point out the institution's development came largely because the U.S. helped block reforms to the IMF that would have given China more influence.

Bove, too, believes the U.S. is "overplaying" its global influence.

"The result of its actions both internally and externally has been the creation of an entity that can compete with the IMF and World Bank internationally; an entity controlled by a country that is seeking to reduce the United States hold on the world financial markets," he said in a report for clients. "The creation of the AIIB also demonstrates clearly that not only are the U.S. enemies but also its biggest allies fed up with the United States demands and tactics in the financial world. This is incredibly dangerous to this country's standing internationally in an area where it counts — finance and the dollar."

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In the above I think they are mainly talking about things like these attacks on foreign institutions like BNP Paribas and Commerzbank and legislations like the TIEAs and FATCA and so on. These are hugely onerous legislations and it looks like everyone wants to cut loose of them by shifting to a new system that isn't US controlled.