Hi,
I am a Israeli doing a post don in the USA on J-1 visa.
I was told that since the period between my arrival to the USA and my visa expatriation is more than 2 years (in few days... ) I should pay full tax from day 1.
Is that true?
Thanks
Orna

Unfortunately, yes. I do believe that the U.S.-Israel Tax treaty DOES have a retroactive tax provision in it.

Here is the link; look under Article 23 and 24

http://www.irs.gov/pub/irs-trty/israel.pdf