That's true of basically 85% of the world. The only really independent countries, as far as I can tell are the US, China and Russia with France, Germany, UK and India on the edge.
I'm not sure what your point is unless you think the US will suddenly reverse its centuries old policy and start colonizing the world.
That's precisely why the argument of "if we tax the rich they'll just take their wealth elsewhere" doesn't stack up. If it happens, when it happens, it happens because we made a conscious decision to enable it.
He must not have snapped very loudly, because the only way to buy chewing gum to this day is as medicine (e.g. nicotine gum) from a doctor or pharmacy.
Singapore is not just dependent on the US. It depends heavily on China too. Defense wise, Singapore has one of the strongest forces in the region.
And most millionaires in Singapore are Singapore citizens.
Singapore's status is not just some offshore tax haven, as seen by many in the west. It has a diversified economy.
Singapore exists at the behest of the United States. Its sovereign wealth fund is heavily invested in the United States and its geopolitical precariousness on the straits of malacca is predicated upon the implicit protection of the United States Navy.
It's a political choice to let millionaires flee there, just as it's a political choice not to tax them at home. A snap of the US's fingers will change Singapore's policy.
Like when Wrigley sent a US Congressman to visit - he snapped his fingers and chewing gum was no longer banned.