Over the past five decades, the United States has become intimately involved in the politics of the Middle East, from alliances with Israel to weapons supplied during the Iran/Iraq conflict to more recent incursions in Iraq. Through all of that involvement, the United States and Israel have remained staunch allies. Additionally, Israel buys much of its weaponry from the United States. However, the United States has attempted, at various times, to mediate between the country of Israel and the territory of Palenstine. Although this has achieved, at times, fleeting success, mediation has not led to long-term peace.
The decision the United States has made to support Israel as heavily as they have makes it difficult for the rest of the world to openly support Palestine's efforts to take their land back and stop Israel from encroaching on their rightful territory, and those who support Palestine are considered enemies of the United States.
I think Israel has much greater strength simply by having the support of the United States. I also believe this has a huge impact on their ongoing conflict with Palestine. Any nation that has the support of a super power such as the United States is automatically in a stronger position. I believe Palestine is less aggressive in the current conflict than it would be if Israel did not have the US backing them.
America is the most powerful nation in the world. Because of this, the side we decide to help has a huge advantage over the other in whatever conflict it might be. In this conflict, when we decided to help Israel it automatically put Palestine on the bad side of the conflict.
Yes, the US support of Israel has a large impact on the Israeli-Palestine conflict, because it makes Israel that much more credible militarily. The United States has a strong military, and with their backing, Israel is seen as that much more of a force to be reckoned with. Other nations cannot challenge Israel as much as they otherwise would without US support.