1. First there is timing. The U.S. could have said the same thing about wanting to avoid deadlock and a two month delay in response to Pal insistence that there be a settlement freeze. That demand is just as much a pre-condition as is the Israeli demand that Israel be recognized. The Pal demand can and probably will delay, if not derail, the negotiations. It wouldn't, of course, if there was a reasonable trade-off of significance. 2. The fact that the U.S. recognizes Israel as a Jewish state is important, very important. But it is also not the point. Israel needs that form of recognition with the part(ies) it is at war with. The U.S has recognized Israel as a Jewish state for some time during which Pals have terrorized the state. The Pals could come back and indicate that they are prepared, as an interim step to recognize the state of Israel and negotiate other demands. In the meantime it would be easy for Israel to modify its constitution to provide its self with assurance the Jewish character of the state would be assured. For example, the Constitution could be amended to say the Israel is a Jewish state with the following attributes or requirements ..... And then to provide that alteration of those requirements require the approval of 75% (just to take a figure out of the air) of both the Jewish and non-Jewish population.
Israeli troops shoot, injure Palestinian crossing Gaza border fence (Haaretz)
from the article: U.S.: We want clear path, not two-month delay of peace process deadlock