isn't that exactly what Hitler did in the first place?

Realizing you probably intended it as a rhetorical question, I'll give you an uncommon and serious answer anyway.

It depends on what you believe.

The NSDAP apparently believed that they were defending Germany, Germans and their interests, which had been unjustly, violently abrogated in the great war incited against them by France, Imperial Russia, Great Britain, and eventually joined by the United States. They believed the 'Entente Cordial' and 'Triple Entente' were anything but cordial, that the later self styled allies falsified its causes and odiously wrapped themselves in cloaks of 'Christian hypocrisy' while slowly but surely leading 'mankind to war'. A war they didn't lose on the field, but were unable to win against all and the US, perfidiously betrayed during honorable negotiations, maliciously maneuvered into a Carthaginian peace.

To them, the invasion of 'Poland', was a predictable and necessary restoration of their historical territory, rights and sphere of influence. 'Poland' never existed prior to world war one. It was land torn from Germany, Austria-Hungary and an aggressive and expanding slavic Russian Empire, created and propped up violently. But for the Great war, 'Poland' may never have existed. It was liberating the stolen German homeland and citizens from their state of criminal usurpation by the cabal of powers who'd conspired against her, humiliating her at the time of her greatest weakness and need.

Why should Germany be concerned with such an artificial ahistorical 'border' state created to divide Germans (including Austrians) against themselves, buffers convenient only to their historical and cultural enemies? Similar to Afghanistan and Belgium, among other falsely born pseudo-states.

So to answer your question, perhaps poorly

isn't that exactly what Hitler did in the first place?

That depends on what you consider pertinent historical facts, and how you gauge their relative importance and relation.

People don't tend to reasonably consider the legitimate grievances of enemies, especially after their utter destruction. Who mourns for Hannibal and Carthage, and Vercingetorix and Gaul?