Everything is easy in hindsight. You seem to be advocating for the annihilation of Israel?
The Holocaust put paid to the idea that anti semitism and jew hatred was a thing of the past - and we still see it continually bubbling both above and under the surface in mosques and in Left wing rhetoric today.
The land did not belong to the tribes that lived there pre 1948; It was part of the Ottoman Empire. The semi nomadic peasants who eked out a living had to pay land taxes to the Ottomans. The wealthier arabs lived in the cities of Beirut, Damascus and Aleppo - the region was seen as a backwater - with a large area of infertile land ( the Negev desert).
There are not 100% conscription rates. But even if there was, so what - lots of countries implement national conscription (or service) including Switzerland, Denamrk, Turkey to name a few; and in fact the EU has recently floated the idea of bringing back conscrption to everywhere in Europe in the face of a growing likelihood of war with Russia.
The plan was always a two state solution - but that was rejected on numerous occasions, and until the leaders of 'the Palestinians' accept the existence of Israel and stop with the fantastical idea of " from the River to the Sea" there can be no peace. It would not involve displacing anyone other than the current Israeli settlers on the West Bank.