Anyone who has served in the USA and have had a child there and exercised their right to claim a US passport for them, beware. Upon age 18 wherever that child lives and works, they will be liable for tax on earnings . To avoid this, you need to visit a US embassy, renounce US Citizenship and pay $2500 for the privilege and of course, pay back any tax outstanding. Dual nationality is not recognised. Some horror stories starting to crop up. Eg 28 year old left the US when he was 1, took family to Disney and was arrested at immigration for tax evasion and hit with a six figure bill!