Pretty sure Israel maintains a stable and official border. Just try to enter by car, you will realize there's a border.

I think they meant Israel keeps changing their borders by taking other countries' territories by force.

No I meant exactly what I wrote, that Israel does not have official borders. In the example of the comment you replied to, if you try to cross any number of unofficial, illegal, and moveable borders in the vicinity of Israel, Israel might or might not shoot you, depending on who you are, who they think you are, and the mood of the day.

Why? Because if they said what their border are, they would be already implicitly renouncing to anything outside them, or at least recognising that they don't have a right to it. Why set limits to your ambition?

It's the other way round: They have a strong incentive to define what's outside of their border (and therefore defining their border), because people living within their border would end up having more rights.

That's also the reason why they never annexed Westbank and try to get rid of the people living there.

It is also the other way around: Israel doesn't have any incentive to formally annex a territory that is full of Palestinians because that would make it more complicated to deprive them of rights (as they did with the residents of Jerusalem).

But Israel also doesn't have an incentive to define a narrow permanent border and therefore renounce more territory acquisitions. For example, illegal settlements outside the internationally recognised borders are defended and taxed as territory of the State; their residents are considered residents of Israel.

So the solution is to keep vague and say that borders are "contested".

No, it doesn't. Did you even check before writing this?

> Just try to enter by car, you will realize there's a border.

If you mean "Israel borders are wherever they shoot families on cars" that is pretty wide, going from the south Lebanon to Gaza and the whole West Bank. But since that changes every day, that's not a border. If you ask them, they will also say it's not a border.