>1920s Russian invasion failed but also was bad.
That's a very interesting turn of conversation. I think you are missing a bit from that story when presenting Poland as a victim[0]:
According to Aviel Roshwald, (Piłsudski) "hoped to incorporate most of the territories of the defunct Polish–Lithuanian Commonwealth into the future Polish state by structuring it as the Polish-led, multinational federation." Piłsudski had wanted to break up the Russian Empire and set up the Intermarium federation of various different states: Poland, Lithuania, Belarus, Ukraine and other Central and East European countries that emerged from the crumbling empires after World War I. In Piłsudski's vision, Poland would replace a truncated and vastly reduced Russia as the great power of Eastern Europe. His plan excluded negotiations prior to military victory. <...>
He used military force to expand the Polish borders in Galicia and Volhynia and crush a Ukrainian attempt at self-determination in the disputed territories east of the Curzon Line, which contained a significant Polish minority. On 7 February 1919, Piłsudski spoke on the subject of Poland's future frontiers:
"At the moment Poland is essentially without borders and all that we can gain in this regard in the west depends on the Entente – on the extent to which it may wish to squeeze Germany. In the east, it's a different matter; there are doors here that open and close and it depends on who forces them open and how far".
Polish military forces had thus set out to expand far in the eastern direction. As Piłsudski imagined,
"Closed within the boundaries of the 16th century, cut off from the Black Sea and Baltic Sea, deprived of land and mineral wealth of the South and South-east, Russia could easily move into the status of second-grade power. Poland, as the largest and strongest of the new states, could easily establish a sphere of influence stretching from Finland to the Caucasus".
>that joint invasion of Poland by Russia (Soviet Union) and Germany (Third Reich)
The USSR returned the territory that Poland grabbed in the 1920. And I must remind you that just a year earlier Germany, Hungary and Poland jointly dismembered Czechoslovakia[1]:
Germany had started a low-intensity undeclared war on Czechoslovakia on 17 September 1938. <...> This was followed by Polish and Hungarian territorial demands brought on 21 and 22 September, respectively. <...> Poland grouped its army units near its common border with Czechoslovakia and conducted an unsuccessful probing offensive on 23 September. Hungary moved its troops towards the border with Czechoslovakia, without attacking. The Soviet Union announced its willingness to come to Czechoslovakia's assistance, provided the Red Army would be able to cross Polish and Romanian territory; both countries refused.
<...>
The Munich Agreement was soon followed by the First Vienna Award on 2 November 1938, separating largely Hungarian inhabited territories in southern Slovakia and southern Subcarpathian Rus' from Czechoslovakia. On 30 November, Czechoslovakia ceded to Poland small patches of land in the Spiš and Orava regions.
[0] https://en.wikipedia.org/wiki/Polish%E2%80%93Soviet_War#Back...
[1] https://en.wikipedia.org/wiki/Munich_Agreement