401k or Roth IRA for non treaty countries

This might be a bit complicated, so pretty please bear with me a little.

• I am currently living in USA on a E2 visa.

• My employer offers both 401k and Roth IRA.

• I do not plan to neither retire nor live in USA in the long run.

Should I contribue to 401k?

The problem:

• I hold two citizenships. Country A and Country B.

My E2 visa is with Country A, that does not have a tax treaty with USA.

My other citizenship in Country B does have a tax treaty with USA.

When I retire, I will most probably live in Country B. Will the 401k be subject to the tax treaty of my current residency?