My first thought on hearing Bibi might call for September elections is that he (presuming he retains power) would then be able to bomb Iran claiming a mandate from the Israeli voters to do so. He would be assured of full-throated support of the Republicans in the United States, and likely embarrass Obama -- which, if the US presidential race is tight, could throw the election to Romney, and possibly the Senate to the Republicans as well. Yes, he is that cynical.
10 arrested at Israeli Arab protest in Ramle (Haaretz)
from the article: Israeli elections likely to postpone any deliberations on Iran strike