Legal Question in Tax Law in Massachusetts

If you are a US citizen you are subject to US income taxes on your worldwide income. I do not know how you have a US passport without a social security number but you should file US income tax return.

You get a tax credit for all income tax paid to foreign governments

Being deemed an ex-pat has a number of other special tax credits and benefits

This is going to cost you a packet to make right. The possibility always exists that you get snagged on entry into the US; criminal prosecution is possible, and it would be unwise to take the risk. The fact that you do not have any assets in the US means that as a practical matter the IRS cannot satisfy any tax liabilities by garnishment or attachment; they also are unlikely to be able to generate returns for you because they would have no data on your foreign-source income. So, as a practical matter, if you never return to the US there is no reason to embark on the process.

If you do intend to travel to and from the US, then you need to contact a US lawyer who in turn would engage a CPA to prepare all the delinquent returns. If you have been living in a jurisdiction with high taxes and a tax treaty with the US, then you may not have any significant tax liability (as Mr. Roth observes, you get a credit for taxes paid overseas), so the real expense may be in preparation of all these returns.

Best wishes,

LDWG