No. Israeli Prime Minister Benjamin Netanyahu has been misquoted across the political spectrum:
The leftist Mondoweiss, the establishmentarian Foreign Policy, and right-skewing PJ Media have all made this mistake. I don’t speak Hebrew but I’m pretty sure Netanyahu was not referring to Dallas, nor to the embankment in downtown Dallas where 21 cops thought they heard gunfire on November 22, 1963.
Here’s the story:
In responding to a Jeffrey Goldberg report that an unnamed Obama White House official had called Netanyahu “chickenshit,” the right-wing prime minister gave a speech to the Israeli Knesset:

According to Haaretz, the leftist Israeli daily, Netanyahu said: “”When there are pressures on Israel to concede its security, the easiest thing to do is to concede. You get a round of applause, ceremonies on well-kept lawns [bold face added], and then come the missiles and the tunnels.”
The U.S. news reports translated the bold faced phrase as “ceremonies on grassy knolls.”
In this context, the phrase “grassy knoll” doesn’t make much sense, as a threat or even as an image. There are no ceremonies on the spot in Dallas known as the “grassy knoll.”
Indeed last year when Dallas commemorated the 50th anniversary of JFK’s death, the remarkably dull ceremony blocked the grassy knoll from the eye of the world’s TV cameras by filling it with network TV trailers.
I’ll bet my dollar to your doughnut that Netanyahu was referring to the well-manicured White House lawn where Israeli Prime Minister Yitzhak Rabin and Palestinian President Yasser Arafat shook hands on the 1993 Oslo Accords that eventually failed. That would support his point.
More facts about “the grassy knoll”
21 cops who thought they heard a grassy knoll shot.(August 15, 2014)
Missing Witnesses: two African-Americans on the grassy knoll. (September 13, 2014)
Credible Witness: Bill Newman’s story (June 22, 2014)
Actually, Jeff, there are ceremonies (speeches and moments of silence) on the grassy knoll every year, on November 22nd.
But that said, It seems likely you are correct in your assessment of what he was trying to communicate.
Hear Hear Pat Speer, on behalf of the Tunnel Rat from The Midlothian Mirror.
If you look again at the Mondoweiss thread, you will see that Ha’aretz originally had the mistranslation, and then scrubbed it.