Emu Casino is regulated by Curacao and powered by Microgaming casino games. Both Curacao and Microgaming do not accept citizens from the United States of America.
I sent an email to the Emu Casino support to get a clear explanation. Here is their answer :
We don't accept players from the US. If you dont live in the US you can play at our site (pokies, slots,etc.).
As part of the US gambling law, Emu Casino preferred to step back from the US Markets. However, some online casinos still continue to accept US citizens. Check our top 3 US Casinos.
Technically, you could play to Emu Casino if you signed up from abroad. For instance if you are in vacation in Thailand or in Indonesia, you could play to Emu Casino while you drink your White Russian. However, you should not use a US address and an american credit card (from Citibank for instance).
This is the same problem as "signing-up from abroad". You could use a VPN to play to Emu Casino, but you would need to have a real address outside of the US (with phone bill at your name for instance). If you have a relative abroad, for instance in the Ireland, it could work. Otherwise, in case you win a $2,000,000 jackpot, Emu Casino could block your funds..
We know that Bovada is currently accepting US citizens. It is powered by Top Game software and offers a nice welcome bonus.