British voters chose to “leave” the European Union on Thursday, defying the polls — and President Barack Obama, who had pressured Britain to “remain” in the EU. Hillary Clinton followed suit and demanded Britain to stay in the EU. Only Donald Trump had backed the campaign to leave.

Obama’s rather threatening advice may have pushed some voters to “leave.” In April, he warned British voters they would be at the “back of the queue” in trade with the U.S. if they ditched the EU. Some, like Andrew Roberts, took offense, writing in the Wall Street Journal a passionate response with reference to the UK’s assistance during the 9/11 attacks:

“Surely—surely—this is an issue on which the British people, and they alone, have the right to decide, without the intervention of President Obama, who adopted his haughtiest professorial manner when lecturing us to stay in the EU, before making the naked threat that we would be sent “to the back of the queue” (i.e., the back of the line) in any future trade deals if we had the temerity to vote to leave.

Was my country at the back of the line when Winston Churchill promised in 1941 that in the event of a Japanese attack on the U.S., a British declaration of war on Japan would be made within the hour?

Were we at the back of the line on 9/11, or did we step forward immediately and instinctively as the very first of your allies to contribute troops to join you in the expulsion of the Taliban, al Qaeda’s hosts, from power in Afghanistan?

Or in Iraq two years later, was it the French or the Germans or the Belgians who stood and fought and bled beside you? Whatever views you might have over the rights or wrongs of that war, no one can deny that Britain was in its accustomed place: at the front of the line, in the firing line. So it is not right for President Obama now to threaten to send us to the back of the line.”

Trump promised in May that leaving the EU would not put Britain at the “back of the queue,” and said: “I think if I were from Britain I would probably want to go back to a different system.” He reiterated that support last week, telling the Sunday Times: “I would personally be more inclined to leave, for a lot of reasons like having a lot less bureaucracy. … But I am not a British citizen. This is just my opinion.”