By far the most numerous category of individuals who planned (and tried) assassination attempts on Adolf Hitler were his own generals. His own because they took their oath of allegiance to Hitler personally.
There is a very popular misconception that these generals wanted to do away with Der Führer because they hated the Nazi regime, were appalled by its war crimes and crimes against humanity, etc., etc.
Unfortunately, nothing can be further from the truth. In reality, generals that plotted the assassination of Adolf Hitler (by itself or as part of a military coup) were driven by one fundamental emotion.
Fear. Which some Christian theologians consider the “eighth deadly sin”. The 1938 Oster conspiracy was driven by the fear the Adolf Hitler would drag Germany into the war for which it was ill-prepared. And thus by the fear of the consequences of the defeat in that war that top Wehrmacht brass estimated (correctly) as being far more devastating than the consequences of the First Great War.
Although Henning von Tresckow and his co-conspirators claimed that they developed their assassination plan as early as in 1941, in reality they did only in 1943 when the most far-seeing (forward-thinking) Wehrmacht officers knew that Adolf Hitler would inevitably lose the Second Great War – on both fronts.
Consequently, the only way to save Germany from the worst disaster in its history (by far) was to kill its Führer and replace him with someone who would at least achieve acceptable peace with its adversaries. So they went to work.
On February 19th, 1943, Hitler flew to Werwolf, his “field headquarters” on the Eastern front near Vinnitsa in Ukraine. He stayed there for almost a month, until March 13th (no, it was not Friday – it was Saturday).
On that day, Hitler decided to visit the HQ of Army Group Center (AGC) near Smolensk in Russia en route back to Germany. He intended to meet with AGC commander Field Marshal Günther von Kluge and dine in the officers’ mess before departing. Which created an excellent opportunity for Tresckow and his co-conspirators to finally get rid of their commander-in-chief.
Tresckow had prepared three options for achieving this objective. First, Major von Boeselager (commander of cavalry “honor guard near AGC headquarters) had secretly packed his unit with anti-Nazi officers who were ready to kill him to save Germany.
With this force he could intercept Hitler in the forest between the airfield and the HQ area, overwhelm Hitler’s SS escort in a fair fight, and kill the Führer. This option was rejected because (1) the plotters disliked the prospect of German soldiers fighting each other, and (2) because the attack could fail if the escort was stronger than expected.
Given the attitude of plotters towards LSSAH (Hitler’s SS bodyguards), I strongly suspect that only second factor made the former reject this option.
The plotters could shoot Hitler during dinner in the mess. This option was also abandoned for many of the plotters allegedly abhorred the idea of shooting an unarmed man and would not go along.
Again, I seriously doubt that this was the case because if blowing up an unarmed man (together with a dozen of totally innocent Wehrmacht officers and five Luftwaffe airmen) was OK with them, then shooting Hitler in the officers’ mess was fine as well. IMHO the reason why they abandoned that option had nothing to do with morals – Hitler was simply too well-protected by LSAAH and the local Wehrmacht and Waffen-SS personnel.
So they followed the established tradition and chose… the bomb, of course (this episode was skillfully re-created in 2008 movie Valkyrie). The bomb was based on British plastic explosive, which had been seized by the Abwehr from captured SOE agents (proving that much-hyped Abwehr was totally incompetent in this department).
The pencil detonator consisted of a thin copper tube containing copper chloride that would take about ten minutes to silently eat through wire holding back the spring-loaded firing pin from the percussion cap. This mechanism provided a conveniently silent time delay for detonation, without any telltale ticking of a clockwork mechanism or smell from a burning fuse.
The bomb was disguised as a box supposedly containing two bottles of Cointreau. Tresckow was acquainted with Lieutenant Colonel Heinz Brandt, an officer on Hitler’s staff, who traveled on Hitler’s plane.
Tresckow asked Brandt to take the parcel with him to Germany for delivery to Tresckow’s friend General Helmuth Stieff. (Stieff was anti-Nazi, but not a part of the assassination plan). Tresckow claimed the liquor was the payoff for a bet he had lost to Stieff.
Tresckow’s aide, Schlabrendorff, carried the parcel to the airfield. As Hitler and his entourage prepared to board his plane, Schlabrendorff secretly activated the detonator with a pair of pliers, then re-closed the parcel and handed it to Brandt as he boarded the plane.
The bomb was expected to explode about half an hour later, with the plane near Minsk, close enough to the front for the plane’s loss to be attributed to Soviet fighters.
When the crash and Hitler’s death were reported, General Olbricht (Chief of the Armed Forces Replacement Office) would use the Replacement Army to seize control in Berlin, Vienna, and Munich, and in the centers of the Wehrkreis (the German military supply system).
This plan was not just naïve, but suicidal, because (1) the Replacement Army had no authority to seize power in the case of Adolf Hitler dying in plane crash; and (2) a week after the start of the Soviet invasion, Hitler had issued a decree naming Hermann Göring his successor (i.e. the Führer of Germany) in the event of his death.
As the conspirators had no plan to assassinate Göring (and the latter being in full control of the Luftwaffe communication system), the Replacement Army would have been crushed within hours by the troops loyal to the new legitimate leader of Germany.
However, as with Elser’s bomb in 1939 and all other attempts, Vorsehung (“Providence”) had very different plans for Adolf Hitler. So it protected him again. The British-made detonator had been tested many times, was considered reliable and operated correctly in this case as well… but the bomb for still unknown reason did not go off.
Displaying impressive self-confidence, Schlabrendorff took the next plane to retrieve the package from Brandt before the bomb was discovered or eventually detonated late. The explosives were later used by Gersdorff (a week later) and von Stauffenberg (on July 20th, 1944).