I'm a US citizen, but I live in Japan. I have an after-tax retirement annuity in the US. When I receive annuity money, which country gets to tax it?

Thank you.  I'm aware of the US-Japan Tax Convention (treaty) and I have gone through it carefully many times.  There is no clear answer that I can find.

The treaty is contradictory.  For example, one section (Article 17) says that "social security payments... beneficially owned by a resident of a Contracting State shall be taxable only in that Contracting State." In my case, that would be Japan.

However, right at the outset of the treaty (in Article 1), there is the so-called "saving clause" that basically says I'm not entitled to the benefit of Article 17.   That means I am subject to U.S. taxation of my social security payments.

So I'm back where I started... I'm obligated to report my Social Security income to both countries for taxation.

You mentioned Article 23.   I've looked.   Article 23 (3)(a) seems to say one thing, and Article 23(3)(b, c) seems to say the opposite.

That means I still need to figure out which country gets to tax me first, and which one has to allow me to claim a tax credit.   I cannot be the first US expat in Japan who has had to solve this.  There must be a simple answer.

By the way, claiming a tax benefit using the tax treaty would necessitate attaching IRS Form 8833 to the US return to disclose use of the tax treaty and to state specifically which part of the treaty is used.   Do you know what section of the tax treaty TurboTax cites on Form 8833? 

Thanks, again!