You post, "You could at most apply the notion bombardment to tactical air bombardment of a city defended by ground forces." Why? As explained twice above, the Hague Conventions don't specify what weapons can or cannot be used or where they can be delivered from. They just specify that the bombardment of a place declared "Open", and acting in conformity with that, is illegal. Dresden could have been declared "Open" but Hitler would not countenance that anywhere, not just there.
You say, "The indiscriminate strategic bombardment of enemy cities in the midst of a country far away from any fighting was something that was not imagined yet in 1907." It was imagined by the German military, who were sponsoring (if reluctant to pay for) the development of the Zeppelin, three of which already existed in 1907, but it was still apparently remote. Yet, within eight years Zeppelins were undertaking "strategic bombardment of enemy cities in the midst of a country far away from any fighting".
You say, "Even In 1945 the bombing of Dresden was very controversial." Yup, it was even raised in the British parliament and reflects well on British society that this could be discussed openly even while the war was still on. (I see no equivalent public soul searching in Nazi Germany. Do you?) However, it doesn't mean the controversy was justified. In fact, it was a triumph for Goebels, because it was based on his massively falsified 250,000 dead announcement. As already explained to you above, Dresden was full of dozens of legitimate targets and, as long as it wasn't declared "Open" and the war continued, it was an entirely legitimate target.
You post, "The type of bombing practiced by US bombers achieved more and killed much less civilians." The former is certainly true of the targeting of oil and ball bearing production, but again I would ask where is your hard evidence that they killed less civilians? In many major raids the Americans bombed in daylight exactly the same area targets as the British did at night, including at Dresden. Even in daylight, only the first bombers on target might have, weather permitting, have a clear view of it.
You post, "Actions of officers have to be judged without hindsight and for German officers Hitler was the legal head of state of Germany." Nope. All judgements of any sort can only ever be in hindsight. (Prejudgement is not generally recommended.) That said, it is true that for most "German officers Hitler was the legal head of state of Germany." Whether they were right to be so unquestioning is another matter.
You post, "No reason to depose him." Hmmmm. the so-called "Holocaust" doesn't give you pause to question that? General Blaskowitz was already questioning the SS's murder of Jews in Poland before the end of 1939! Was he wrong to do so? I don't think so. Do you?
You post, "You would be hard put to find evidence that Hitler did not have the support of the people." Similarly, in the absence of any freely contested elections or independent opinion polls, you would be hard pushed to definitively prove the opposite. However, anecdotage tends to indicate that Hitler probably did have clear majority support among Germans in the second half of the 1930s, and very probably significantly more than the minority of votes he turned into outright dictatorship in 1933. More fool them!