https://www.gatestoneinstitute.org/16172/israel-borders-law
Today’s Palestinian children are taught to hate Jews and glorify — and handsomely profit from — violence against them.
It is common today to find references to Palestine as a mainly Muslim Arab state that has supposedly been “stolen” by Jews, or promised but not given to those people who describe themselves as Palestinians. That is an immense misconception, albeit one that seems to influence political and legal thinking internationally, especially among people who would like to believe it.
In a clearer understanding [of international law], Israel’s planned move appears to be legal.
“The Palestinian people does not exist. The creation of a Palestinian state is only a means for continuing our struggle against the state of Israel for our Arab unity. In reality today there is no difference between Jordanians, Palestinians, Syrians and Lebanese. Only for political and tactical reasons do we speak today about the existence of a Palestinian people, since Arab national interests demand that we posit the existence of a distinct “Palestinian people” to oppose Zionism…. [T]he moment we reclaim our right to all of Palestine, we will not wait even a minute to unite Palestine and Jordan.” — PLO leader Zuheir Mohsen, the Dutch newspaper Trouw, March 31, 1977.
In general, taking territory from another country is treated under international law as illegal. Much of our sense that such illegality is as much morally wrong as it is legally prohibited comes from historical realities in modern history. The Nazi German takeovers of numerous countries across Europe between 1938 and 1945, together with the brutality with which they were carried out, stand even today as notorious examples of unacceptable behaviour in an attempt to dominate other peoples without the least pretence of legality of purpose or practice. More recently, the Russian Federation’s 2014 invasion of Crimea has caused unnecessary conflict with Ukraine and damaged Russia’s own international reputation.
Article 2 of the first chapter of the United Nations Charter declares:
“All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.”
This was formulated in 1945, in a very understandable response to the aggressions by Nazi Germany. It remains a valid ruling on the dangers posed by powerful nations should they too choose to use force to take over neighbouring territories. Even so, Article 2 was contravened by China in 1959 when it overran Tibet; by Turkey in 1974 when it invaded northern Cyprus, and is constantly contravened by Iran — with the evident complicity of most of the members of the UN — in its expansions into Iraq, Syria, Yemen ad Lebanon, as well as its 41-year-long threats to obliterate a fellow UN member state, Israel.