Objectively speaking, "NATO's eastward expansion" is only a strategic "expression" rather than a conceptual "definition". For example, it is not impossible to call it "Eastern Europe's westward expansion".
In fact, whether it is called "NATO's eastward expansion", "NATO's northward expansion", "Eastern Europe's westward expansion", or "NATO expansion", it is not "neutral" and is not enough to cover its essence, and only "NATO's expansion" is the most accurate neutral description.
And the reason why there is such an expression as "NATO's eastward expansion" is nothing more than highlighting the strategic priorities. The essence of this is that what kind of name is beneficial to oneself will be described accordingly.
In fact, the reason why there is such an "expression" as "NATO's eastward expansion" is that after the collapse of the Soviet Union, some countries of the former Warsaw Group and the former Soviet Union chose to join NATO. This is obviously not good for Russia and other countries, so there is the talk of "NATO's eastward expansion". However, from NATO's point of view, it is just an expansion of the bloc.
In just a few years between 1999 and 2004, 10 countries, including Poland, the Czech Republic, Hungary, Bulgaria, Romania, Slovakia, Slovenia, Estonia, Latvia, and Lithuania, joined NATO. These countries are located in the eastern part of Europe and are linked to the former Soviet Union. Based on strategic considerations, the non-Western camp calls it "NATO's eastward expansion".
Calling it "NATO's eastward expansion" is obviously intended to highlight NATO's "initiative" and even imply NATO's "aggressiveness." However, if we analyze NATO's "accession conditions" and "accession procedures" in conjunction with NATO's "accession procedures," there may be another interpretation.
All 10 of these countries went through a multi-year application and approval process before they were able to join NATO. In addition, Hungary, a small country with a population of just over 10 million, can make Sweden wait more than a year to become a full member of NATO, which shows that it is not forced, that NATO has a threshold, and that NATO is not a "one-word" organization.
So, why did these Eastern European countries "squeeze their heads" to join NATO, a military organization? Obviously, they "have some plans." Because they think NATO will be able to protect them. Therefore, it is not impossible to call it "the westward expansion of Eastern Europe".
In fact, Russia also had the idea of joining NATO, and even had an "application". Therefore, it is of no practical significance to dwell on the nature of NATO as an organization. What we should think about more is, why did these former Soviet blocs and former Soviet countries join NATO without hesitation, and why did Russia not have such an "attraction"?
To put it bluntly, no matter what kind of organization NATO is (even if it is aggressive), there are some facts that cannot be denied. For example, since NATO's founding on April 4, 1949, no country has withdrawn from the organization (France has only withdrawn from NATO's military system, but not from NATO); so far, no NATO member has been expelled or beaten by NATO itself; and so far, no NATO member has been beaten by "outsiders". Perhaps, this is the "attraction" of NATO.
The Soviet Union dominated and established the "Warsaw Group" in confrontation with NATO, however, this bloc later became the "Yiyantang" organization. So, Poland, a member of the Warsaw bloc, was "forced", Czechoslovakia was "beaten", and Soviet tanks were driven into Budapest. Perhaps it is based on this that after the collapse of the Soviet Union, Poland, the Czech Republic, the Baltic countries quickly fell to NATO.
After Ukraine, which is not a member of NATO, was beaten, Russia's two neighbors, Finland and Sweden, which had been "neutral" outside the two major military blocs for decades, joined NATO without hesitation.
In the arena of public opinion, some people often raise the following question: NATO was established to deal with the Soviet Union, and after the Soviet Union collapsed, why did NATO not dissolve and who it was going to deal with? As early as the beginning of NATO's founding, then British Foreign Secretary Bevan had an "interpretation" of this issue.
After the creation of NATO, the Soviet Union expressed strong opposition, believing that it was directed against it. In this regard, the then British Foreign Secretary Ernest Bevan said that NATO does not have a specific target, but a protection measure against future aggressors, and if the Soviet Union believes that it is directed against it, history will prove that it should be targeted. In fact, this also answers the question of who NATO is targeting now.
History has no ifs, but it is also worth assuming that if Poland and the three Baltic countries were not members of NATO, would they have suffered the fate of Ukraine as it is now? Perhaps, they would have suffered worse than Ukraine.