Honest question, is a country's right to exist enshrined by UN Law? How is 'country' defined? What i mean is that, say if France has a legal right to exist, and it annexed the channel islands and called them their own, does that mean, legally speaking we have to recognise France with it's updated land mass' right to exist? If the UK tried to get them back by force and France levelled London because they weren't respecting France's right to exist? Can one country's 'right to exist' usurp another's? Are there other examples of this in history? Since WW1 about 20 countries have disappeared, and probably the same number created, so there must be a fair about of inter country tension globally.
Also the self determination issue, if Israel bases part/all/some of it's claim that it has the right to occupy the land (outside of the legal basis of its creation) based upon ancestral/religious linkage, does the same not apply to first nationers in Australia and USA? Or if it's due to cultural identity the same would apply to Kurds, Basques & Catalans.