Boiling down the Night of the Long Knives to a single motive is nearly impossible, there were many reasons why it was beneficial to purge the SA, not least because of their growing rowdiness which was developing into a crisis. Hitler had, in the case of the Stennes revolt in 1930, averted a crisis without bloodshed that was similar to that faced in 1934, and Hitler attempted to solve that situation by peaceful means in 1934 also, by meeting with Röhm and attempting to get him to change his course. This didn't happen. Thus, as is well known, Hitler had to be pushed into taking drastic action against Röhm and the SA leadership, even though he didn't desire to harm his own men who had professed their loyalty to him. This pressure, at least partially, came from the conservative establishment and v. Hindenburg himself, who was considering marshal law unless Hitler made a move.
Hitler did not "murder" anyone:
The biographers, both great and lesser, nevertheless assign the word murder to describe the eventual killing, but the word is more contemptuously pejorative than useful in discussing what took place. First and foremost, the killing of a human being to be classified as murder demands the presence of malice aforethought—the killing must be willful, premeditated, and deliberate. With murder seen as such, Röhm cannot be seen to have been murdered by Hitler, although that would have been scant solace to him, for death is death. Hitler had shown enormous forbearance with Röhm, and no actions that suggest malice aforethought could be seen on Hitler's part through mid-June. Toward the end of June, however a latecoalescing quadrumvirate of Goering, Himmler, Heydrich, and Goebbels fed Hitler report, document, and rumor of an impending SA putsch. During the same period and specifically in his meeting of June 21 with President Hindenburg and Werner von Blomberg, Hitler would receive an ultimatum to the effect that “internal peace was the first priority. If Hitler could not remove the present intolerable tension... the president would declare martial law and turn the job over to the army.” At this moment, Hitler would have faced the necessity for decisive action, including the possible killing of Röhm, to halt the impending disaster of army intervention.
R.H.S. Stolfi, Hitler: Beyond Evil and Tyranny (New York: Prometheus Books, 2011), Pp. 306.
What sealed the fate of both Schleicher and Gregor Strasser was the fact that Schleicher had offered Gregor the vice chancellorship in a government purged of Hitler, which he accepted. However, Hitler had not decided to kill either of them, this action was taken under Hitler's nose. Schleicher's step daughter and Gregor's widow were both provided monetary compensation for their losses. (Irving, True Himmler, p. 277, 303.)
Purging the SA had nothing to do with pleasing "Prussian elites" and wanting to "wage wars", perhaps some historians have made this erroneous suggestion. Hitler biographer Volker Ullrich attempts to show this, but nonetheless what he quotes from Hitler is the discussion of the SA's incapability to defend
the Reich, not his desire to unleash a conflict:
A militia of the sort suggested by the SA chief of staff, Hitler said, “was unsuitable even for the smallest national defensive action,” to say nothing of the future war for “living space” he again put forward as a vision. For that reason, he was determined to raise “a people’s army, built up on the foundations of the Reichswehr, of thoroughly trained soldiers equipped with the latest weaponry.” The SA was to subordinate itself to his orders. There could be no doubt, Hitler concluded, that “the Wehrmacht is the only armed force of the nation.”
Volker Ullrich, Hitler: Ascent 1889-1939 (London: The Bodly Head, 2016), Pp. 461-462.
The fact is, Hitler wanted to maintain the support of the Army because he knew that the SA was simply not up to the same task as the disciplined and professionally trained Reichswehr
. Germany couldn't defend herself, or establish her claims abroad with a sub-par and defiant army made up of men who had no military training or experience whatsoever.
Not only did Hitler intervene personally to arrest Röhm and various other SA leaders, but even after he had been forced to sanction the excess killings that he didn't authorize, he himself took full responsibility:
Meeting on Tuesday, the Cabinet heard Hitler’s account. Speaking ‘in all their names’ General von Blomberg welcomed the Chancellor’s ruthless action. Hitler said the Reich had teetered on the brink of an abyss. The Cabinet minutes record that he accepted full responsibility, ‘even if the degree of blame had not been established in every case, and even if he had not ordered all the executions by firing squad.’
David Irving, True Himmler (London: Focal Point Publications, 2021), Pp. 282-283.
Hitler came out of this much respected by the German people, his popularity reached new heights. Any attempt to frame the Night of the Long Knives as a show of "terror" from the regime, to set an example or whatever, also has no basis in fact. Hitler's actions were widely supported:
The initial uncertainty people felt when they heard the news of the murders on 30 June soon gave way to relief. The SA men, who had been so welcome when suppressing the political Left in early 1933, had used up all of their credit among the general populace with their disorderly conduct. The bloody excesses of the SS were excused because they had helped remove an unwanted source of disruption. Goebbels was probably exaggerating when he noted: “A limitless enthusiasm is passing through the country.” But it is true that, far from losing prestige, Hitler’s reputation had improved. This is reflected in a number of Nazi Party reports on the mood within the population. Among the broad masses, and particularly among those who took a wait-and-see attitude towards the movement, Hitler has achieved a great victory with his decisive action—he is “not only admired; he is deified,” read one report from a small industrial town in Upper Bavaria. Immediately after the Night of the Long Knives, Luise Solmitz noted in her diary: “The personal courage, the decisiveness and effectiveness [Hitler] showed in Munich, that’s unique.” Neither Solmitz nor the majority of the German people were bothered by the state planning and carrying out acts of murder—a clear indication of how dulled people’s sense of right and wrong was after only one and a half years of Nazi rule.
Ullrich, op cit., p. 471.
Generally the Night of the Long Knives is characterized by people who don't know better, or historians that do but want to smear Hitler, as an act undertaken to cement Hitler's authority, which was never in question anyway. So that cannot be it:
Unlike Stalin’s Old Bolsheviks, who looked back with regret to the days of Lenin’s leadership, when the party line was freely debated, and who could never in their hearts recognize Stalin as his equal or successor, the Nazi Alte Kämpfer might grumble but never questioned Hitler’s position as Führer.
As a result, Hitler was never troubled by the need for recognition that haunted Stalin, and the Nazi party experienced none of the convulsive series of purges that Stalin imposed on the Communist party leadership. Hitler had no need to pursue a policy of divide and rule; he had no rivals to fear. Both Gregor Strasser and Röhm, although they disagreed with him on policy, recognized they could never replace him. The Röhm purge of 1934 does not contradict this. For the grievances of Röhm and the SA sprang not from their rejection of Hitler, but from their fear that Hitler was rejecting them; while Hitler himself agreed reluctantly to the purge for political reasons, in order to keep the support of the army in securing the succession to von Hindenburg.
Alan Bullock, Hitler and Stalin: Parallel Lives (London: HarperCollins, 1991), Pp. 394.
Some people use the Night of the Long Knives as an example to "prove" Hitler's duplicitous and unprincipled nature, claiming that for the sake of power he would even "murder" his own followers. Yet this explanation has no basis in reality either, and is said to support the claim that Hitler was ruthlessly doing away with political opponents. Which is technically true because Röhm did
What all of these sensational explanations subtly admit, is that Hitler was truly facing a domestic political threat, and since that was the case, regardless of how one describes Hitler's intentions he was justified in taking action against them nonetheless. Where these interpretations fall flat, is that they can brandish no documentary evidence to support their assertions about Hitler's motives. That Hitler was facing some kind of threat isn't disputed, and cannot be if one wants to claim Hitler was weeding out political opponents who were a threat to him.
Hitler biographer Ian Kershaw concurs with Bullock, another respected Hitler biographer, that Hitler's position was "structurally more sound than Stalin's" in Russia, and that he was forced to act against the SA:
Hitler thought Stalin must be mad to carry out the purges. The only faint reflections in the Third Reich were the liquidation of the SA leadership in the 'Night of the Long Knives' in 1934, and the ruthless retaliation for the attempt on Hitler's life in 1944. In the former case, Hitler agreed to the purge only belatedly and reluctantly, after the going had been made by Himmler and Goring, supported by the army leadership. The latter case does bear comparison with the Stalinist technique, though by that time the Hitler regime was plainly in its death-throes. The wild retaliation against those implicated in the assassination attempt was a desperation measure and aimed essentially at genuine opponents, rather than a basic technique of rule.
Down to the middle of the War, Hitler's position lacked the precariousness which surrounded Stalin's leadership in the 1930s. Where Stalin could not believe in genuine loyalty even among his closest supporters, Hitler built his mastery on a cultivated principle of personal loyalty to which he could always successfully appeal at moments of crisis.
Ian Kershaw (ed.), Moshe Lewin (ed.), Stalinism and Nazism: Dictatorships in Comparison (Cambridge University Press, 1997), Pp. 93.
Kershaw thus rejects the comparison of Hitler's purge of the SA and Stalin's irrational, vitriolic and senseless purges which, by the way, would fall under the definition of murder.
Hitler had, after all, only sanctioned the killing of 7 people, not the subsequent 82 which resulted from the action:
Much had in fact happened that unsettled Hitler. Göring had wantonly liquidated Gregor Strasser, Hitler’s rival, and there had been a rash of killings in Bavaria. [...] Hitler’s adjutant Brückner later described in private papers how Hitler vented his annoyance on Himmler when the Reichsführer SS appeared at the chancellery with a final list of the victims – eighty-two all told. In later months Viktor Lutze told anybody who would listen that the Führer had originally listed only seven men [...] Hitler’s seven had become seventeen, and then eighty-two. ‘The Führer was thus put in the embarrassing position of having to sanction all eighty-two killings afterward,’ complained Lutze. Lutze put the blame squarely on Himmler and Göring
David Irving, Hitler's War and the War Path (London: Focal Point Publications, 2019 ed.), Pp. 31. Irving, Himmler, op cit., p. 273, 282.
The Night of the Long Knives was a necessary act, one that Hitler was forced to take not only because the threat was real, or at least, he genuinely believed it was. Many considerations had to be made, and it took Hitler time to deliberate on the best course of action. The repeated offers of peace to Röhm had failed (eg. Rudolf Hess's radio address: Stolfi, op cit., p. 308.
). Hitler was left with no other choice.