HaRav Yosef Eliyahu Henkin zt’l in Kisvei Rav Henkin vol. 2 5719 #109, vol. 2 in the haskomos, vol. 1 #206, vol. 2 p. 103 states “I opposed with all my might the creation of the Medina”. He also quotes that it is against the 3 oaths and that Hashem will punish us for it. He also says that the holocaust came about as a punishment for the violation of the Oaths:
http://hebrewbooks.org/pdfpager.aspx?req=3217&st=&pgnum=115&hilite=
Rav Henkin said that after the against-the-Torah establishment of the State of Israel, the fact is there are now millions of Jews living there and whose safety depends on the physical security of the country, and so nobody should do anything that puts Jews in danger and the fact that the creation of Israel was an aveira is no excuse to support the Arabs. (Of course, nobody disagrees with that. The Satmar Rebbe writes more than once that now that the State is established, we cannot allow the Arabs to take over, and only prayer – and Moshiach – can safely dismantle the State and that we cannot allow the nations to dismantle it because that would be a sakanah for the Jews living there.)
Kisvei Rav Henkin vol 2 5719 #109, vol 2 in the haskomos, vol. 1 #206, vol. 2 p. 103:
“Dechikas Haketz [i.e. one of the three Oaths – not to “pressure the time of the geulah] pushes the time of Geulah further away, and because the different types of Baryonim wielded the sword and participated in various rebellions, one thing led to another and the result was that we lost the majority of our nation, who were killed through horrible deaths, the like of which has never been seen in all of history, and thousands of holy congregations were razed to the ground, and b’avonoseinu harabim it has fueled the warning of Chazal – “and if not [i.e. if you do not follow the Three Oaths], then I shall permit your flesh to be hunted like game in the field” – Hashem should have mercy on those who survived.”
He also adds about how Jews are not allowed to be involved in wars and our approach should be totally one of submission, and how the Baryonim are still involved in antagonizing the nations.
Already we see that the opinion of the Rabbis was hardly monolithic.
The “vote” that the Agudah took where the greatest Gedolim, such as Rav Ahron Kotler and Rav Elchonon Wasserman who were there – (and it should be noted that together with them held Rav Chaim Ozer and the Brisker Rav and Chazon Ish who weren’t there altogether) – were “outvoted” by a greater number of much lesser Rabbonim.