The New York Times in its review of The Darkest Hour refers to the film makers’ sham populism which is at its most evident when showing Churchill riding the London Underground and meeting The People (a motley mass of stiff upper lips and misty eyes).
Charles Moore writing in the Spectator opined that the film indicates when Churchill left Downing Street for the House of Commons to make his ‘We shall fight on the beaches’ speech he did so without knowing what he would say. (In the film) dear, patriotic citizens weepily beg Churchill to declare that we will fight on, so he decides that is what he will say in Parliament.
Obviously, in drama, one must not succumb to ‘the tyranny of fact’, but if you know that Churchill did not travel by tube, that he had thoroughly decided what he would say, that he always prepared his parliamentary speeches pretty much word for word, and that only a madman would go from Downing Street via St James’s Park station to get to Westminster, you cannot suspend your disbelief in the cinema.
The speech contains memorable lines – not just the We shall fight them phrases. In his speech Churchill outlined the immediate history which lead up to the British Expeditionary Force debacle and the Dunkirk evacuation. He highlighted but did not overdramatize the role of the Belgians:
“The king of the Belgians had called upon us to come to his aid. Had not this ruler and his government severed themselves from the allies, who rescued their country from extinction in the late war, and had they not sought refuge in what was proved to be a fatal neutrality, the French and British armies might well at the outset have saved not only Belgium but perhaps even Poland. Yet at the last moment, when Belgium was already invaded, King Leopold called upon us to come to his aid, and even at the last moment we came. He and his brave, efficient army, nearly half a million strong, guarded our left flank and thus kept open our only line of retreat to the sea. Suddenly, without prior consultation, with the least possible notice, without the advice of his ministers and upon his own personal act, he sent a plenipotentiary to the German Command, surrendered his army, and exposed our whole flank and means of retreat.”
Thus, we were betrayed by the Belgian royals and if there ever was a case for a full blooded republican coup, this must be it.
And yet the Treaty of Brussels was signed on 17 March 1948 which established a Western Union Defense Organization which in turn lead to the 1951 European Coal & Steel Community, European Economic Community (predecessor to the European Economic Community and the European Union) all of which would be headquartered in Brussels
Supranationalism does not have to be Socialist and Statist but you can see the advantages to the Belgians (like their Prime Minister Paul-Henri Spaak), it let their country punch above its weight and (hopefully) expunge the memory of their 1940 perfidy.

https://www.theguardian.com/theguardian/2007/apr/20/greatspeeches1