We have found it necessary to take measures of increasing stringency, not only against enemy aliens and suspicious characters of other nationalities, but also against British subjects who may become a danger or a nuisance should the war be transported to the United Kingdom. I know there are a great many people affected by the orders which we have made who are the passionate enemies of Nazi Germany. I am very sorry for them, but we cannot, at the present time and under the present stress, draw all the distinctions which we should like to do. If parachute landings were attempted and fierce fighting attendant upon them followed, these unfortunate people would be far better out of the way, for their own sakes as well as for ours. There is, however, another class, for which I feel not the slightest sympathy. Parliament has given us the powers to put down Fifth Column activities with a strong hand, and we shall use those powers subject to the supervision and correction of the House, without the slightest hesitation until we are satisfied, and more than satisfied, that this malignancy in our midst has been effectively stamped out.
The peroration – quoted below – even at a moment of great apparent danger to British national survival talks not only of national survival and national interest, but of noble causes (freedom, Christian civilisation, the rights of small nations) for which Britain was fighting and for which Churchill thought the United States should – and given time would – fight.[d] The War Illustrated published the speech with the title "'If the Empire lasts a thousand years men will say, this was their finest hour'".
10. The mood of Britain is wisely and rightly averse from every form of shallow or premature exultation. This is no time for boasts or glowing prophecies, but there is this – a year ago our position looked forlorn, and well nigh desperate, to all eyes but our own. Today we may say aloud before an awe-struck world, ‘We are still masters of our fate. We still are captain of our souls. House of Commons, 9 September 1941
Turning once again, and this time more generally, to the question of invasion, I would observe that there has never been a period in all these long centuries of which we boast when an absolute guarantee against invasion, still less against serious raids, could have been given to our people. In the days of Napoleon the same wind which would have carried his transports across the Channel might have driven away the blockading fleet. There was always the chance, and it is that chance which has excited and befooled the imaginations of many Continental tyrants. Many are the tales that are told. We are assured that novel methods will be adopted, and when we see the originality of malice, the ingenuity of aggression, which our enemy displays, we may certainly prepare ourselves for every kind of novel stratagem and every kind of brutal and treacherous maneuver. I think that no idea is so outlandish that it should not be considered and viewed with a searching, but at the same time, I hope, with a steady eye. We must never forget the solid assurances of sea power and those which belong to air power if it can be locally exercised.
Nevertheless, our thankfulness at the escape of our Army and so many men, whose loved ones have passed through an agonizing week, must not blind us to the fact that what has happened in France and Belgium is a colossal military disaster. The French Army has been weakened, the Belgian Army has been lost, a large part of those fortified lines upon which so much faith had been reposed is gone, many valuable mining districts and factories have passed into the enemy’s possession, the whole of the Channel ports are in his hands, with all the tragic consequences that follow from that, and we must expect another blow to be struck almost immediately at us or at France. We are told that Herr Hitler has a plan for invading the British Isles. This has often been thought of before. When Napoleon lay at Boulogne for a year with his flat-bottomed boats and his Grand Army, he was told by someone. “There are bitter weeds in England.” There are certainly a great many more of them since the British Expeditionary Force returned.
Winston Churchill Speech WW2