What is the origin of adding the paragraph of ’Tehilat Hashem’ at the end of Shir Hama'alot? I have heard many people say that they don’t recite this paragraph because they claim that this custom was started many years ago by the ’Anti-zionist’ movement in an effort to make the original paragraph of ’Shir Hamaalos’ sound more general and less zionistic. Nobody I have asked has been able to confirm or deny this or tell me the actual source of this Minhag. So what is the source of the Minhag to say Tehilat hashem at the end of ’Shir Hama'alot?

I don't know when exactly this custom began but one thing is for sure, it was an Ashkenazi custom way before any Zionist movement began, beside the fact these verses have nothing in contrast with Zionism, one can be an enthusiastic Zionist and want to say these verses of praise to Hashem. Some suggest these four Psukim relate to the four Brachot of Birkat Hamazon.