Since the IRS came up with this FATCA (foreign account tax compliant act) in March 2010 and FBAR (foreign bank account report) this is specifically for US nationals working abroad, now they are on hunt for those that have not properly filed and/or disclose bank accounts correctly. There is a credit of $99300 per year tax free then after is taxed at......I believe 30% up to 39.5 % if u cross 250k a year (i think)
Dubai has no double tax agreement with US so u pay uncle sam in full.
I hear Dubai is a tax free country but there are some services that are taxed at 10% and the latest is they are exploring ways to tax more.....so be careful when u accept work overseas.....