First, let's see what happened. Here is an article from New York Post, dated November 15, 2022:
Russian-made missile strike kills two in NATO member Poland
A Russian-made missile crossed into Polish territory and killed two people Tuesday, according to Poland, a blast that threatens to pull the NATO alliance into the Ukraine war.
The strike occurred near the Polish village of Przewodów, some 45 miles north of the Ukrainian city of Lviv and 15 miles from the Ukrainian border, the official with knowledge of the situation told the Associated Press.
The Polish government echoed that assessment, saying early Wednesday morning - Warsaw time - that a Russian-made missile had exploded in the eastern part of the country.
In a statement, Warsaw said that Polish foreign minister Zbigniew Rau had summoned the Russian ambassador and “demanded immediate detailed explanations.”
Polish President Andrzej Duda, however, was more cautious, only saying the missile was “most probably” Russian-made but that was still being verified.
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A missile landed in Poland, and 2 people were killed. It's most likely made in Russia. But, did Putin actually attack Poland with this missile?
Here is an article from the Guardian, dated November 16, 2022:
Poland missile 'unlikely' to have been fired from Russia, Biden says
Joe Biden has said the missile that landed in Poland, killing two people, was unlikely to have been fired from Russia due to its trajectory.
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Asked if the missile was fired from Russia, Biden said: “There is preliminary information that contests that. I don’t want to say that until we completely investigate. But it is unlikely in the minds [sic] of its trajectory that it was fired from Russia.” He added: “But we will see, we will see.”The Polish Ministry of Foreign Affairs described the missile as a “Russian-made” missile, a phrase that could include S-300 ground to air missiles in the possession of Ukraine.
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Ukraine’s president Volodymyr Zelenskiy said Russian missiles hit Poland in a “significant escalation” of the conflict. He did not provide evidence.Russia’s defence ministry denied that Russian missiles hit Polish territory, describing reports as “a deliberate provocation aimed at escalating the situation”.
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Biden thinks that it's unlikely the missile was launched from Russia, because its trajectory does not support the hypothesis. Moreover, Ukrainian military also has Russian-made missiles.
Of course it would be possible for Russian military to launch a missile from another country, say, Belarus. But technical possibility is not enough for this kind of military action. There must be strategic or tactical motivations and justifications.
Who benefits the most from this strike? It's certainly not Russia. Considering Russia is already in trouble with Ukraine, I can't see any reason for Russia to provoke NATO. NATO is 30-country big military alliance, which includes the US. NATO's military capabilities far exceed Ukrainian military forces.
Did Russia crush Ukraine so easily, that it's more than ready to provoke and confront NATO? Certainly not. I don't think Putin is stupid enough to actually order missile strike against Poland.
Maybe time will tell, but I doubt it's Russia.