Great political speeches can change history – Churchill’s promising to “fight on the beaches” with nothing to offer except “blood, sweat and tears”, the funeral oration attributed to Pericles during the Peleponnisian War, Judah’s courageous confession and plea for Benjamin’s life before Joseph in Egypt, and John Kennedy’s inaugural call on Americans to “ask not what you do for your country, ask what your country can do for you.”

But most speeches (good and bad) fall flat as motivators for powerful political action, and are quickly forgotten. Bill Clinton, and even more so, Barack Obama are world-class speech-makers — this skill was a central factor in Obama’s sudden rise to the top of American politics. But as President, Obama failed in most of his policy initiatives, particularly in the international arena. His Cairo speech aimed at the Arab and Muslim world was a ringing statement of hope and a program for action to address issues of poverty, corruption, war and tyranny. But Obama could not translate his words into a realistic strategy, and the region descended from tyranny to anarchy.

Donald Trump, in contrast is often an incoherent and uninspiring orator with a painfully limited vocabulary, and, at best a wooden delivery as he plods through an unfamiliar text. On this scale, his Riyadh speech was one of his best, largely sticking to the script, making some important points. He spoke to the Arab leaders on the urgency of halting Islamist terrorists: “Drive them out of your places of worship. Drive them out of your communities”, and of working Intensively to end “the oppression of women, the persecution of Jews, and the slaughter of Christians.”

But his words will mean nothing if tomorrow, next week, or next month Trump reverts to his usual practice of saying or tweeting the opposite of whatever he said before, or, like Clinton and Obama, confuses speeches with coherent action. Indeed, given Trump’s track record and the chaos in the White House,, I would give his speeches on this trip (including the one scheduled for Jerusalem) minimal weight unless or until he and his administration shows signs of acting on these words consistently, for better or worse.