It was by far the deadliest day of cross-border violence since a devastating 2014 war between Israel and Gaza's Hamas rulers, and further dimmed the already bleak prospects for President Donald Trump's hoped-for peace plan. (IN PIC: In this photo combination, Palestinians protest near the border of Israel and the Gaza Strip, left, and on the same day dignitaries, from left, Sara Netanyahu, her husband Israeli Prime Minister Benjamin Netanyahu, Senior White House Advisor Jared Kushner, and U.S. President Donald Trump's daughter, Ivanka Trump, applaud at the opening ceremony of the new U.S. embassy in Jerusalem on May 14, 2018. /AP Photo)