Advice needed: Amex Plat app hit with 4506T but no tax files

[bondsandloan]

^ Unfortunately the above statement is incorrect. It's a common myth though.
All U.S. residents (don't have to be citizens/LPR) that is those who meet the IRS substantial presence test are required to file US taxes on worldwide income. What the OP is planning to do in respect to his/her taxes is correct.
OP, I won't worry about the 4506-T too much. You probably got hit with it due to your short credit history. Actually the more imp thing to do is that if you have been in the US for only part of the year, is to seek advise of a high end tax accountant & see if you could file non-resident taxes & not get taxed on your global income. If your global income is significant, saving tax on that would be more important than creating tax/credit history in the U.S. But that's just my 2 cents!
And if your priority is just to build that credit history, then no, Amex will not take other proof of income for your foreign sourced income other than that 4506-T so it's 100% better not to poke the bear.
I think if you had applied for that plat with 1+ yr history & higher limits, you would not have been hit with the 4506-T. Think the reason you got it - cause it's algos red flagged you - You have way too low credit limits for your 100k income & credit history for your age, so it doubts your income and wants you to prove it.

[SBR249]

I stand corrected. It is indeed anyone who the IRS considers to be a tax resident who must report all worldwide income. However, it's worth looking into whether bilateral tax treaties exist between the 2 countries that would simplify or waive these requirements. 

[Anonymous]

I believe I will remain non-resident for tax purposes for the first two years and there is in any case a very beneficial bilateral tax treaty that governs my taxes. So, I won't have to pay any US taxes, but probably will have to file, and won't then have any documentation to satisfy Amex until mid-next year.

It's a lesson learned about sprint vs. marathon I suppose. It's just very annoying to have missed this opportunity (likely) to obtain more of the AMEX cards I wanted in the short run. Hopefully I get to keep my Amex Gold...

Thanks for your advice. Sounds like I should not poke the bear.

[bondsandloan]

If you are a non-resident for tax purposes i.e. not paying US taxes on worldwide income, I don't think a 4506-T will generate for you with any income (what Amex cares abt) in the topline. You might need to double check on that one.
You should also tick US non-resident on all your credit card applications in the U.S. - as per my understanding, the system auto declines all non-residents from cc applications. Though I could be wrong!

It is a very tricky road if you are clicking U.S.resident in your credit card apps and filing non-resident taxes. I think Amex 4506-T request caught on to that disparity by chance. I would advise you not to do so just for the sake of some credit cards. You are banking on credit card companies & IRS not exchanging data when you do so and you might be right, that they won't. But it's not a risk I would take!