Well, first of all, as others have pointed out, the Jews are the oldest extant indigenous group of that region. They called that place home, literally thousands of years before the first Arab decided to invade it. So talking about the "colonial" Jews as opposed to the "native" Arabs is kinda ridiculous.

Now, some like to reconcile this, by making up definitions of "native", that put expiration dates on having a homeland. That after some time has passed, the actual natives become the "colonialists" (in the Jews' case, with no actual homeland of their own) and the invaders who took their lands, centuries if not millennia after the fact, become the "natives". That if, say, the Native Americans who were expelled during the Trail of Tears, try to return to their original lands, they'd be "colonialists", while the white settlers who lived there for the past two centuries, would be the "natives".

The problem with that definition is twofold:

1. First of all, it's not very convincing, since it's never been used anywhere else but in this particular case. It's a weird mashup of colonialist and anti-colonialist language, that isn't really coherent.

2. And second, and most importantly, it essentially means "might makes right". As long as one can conquer a land and hold it for a sufficient amount of time, he becomes the "native", and those he took it from, become the "colonialist".

   And that is obviously problematic if you're trying to promote the Palestinians' rights (which you clearly are), since it's the Israelis who have all of the "might" right now. According to that nonsensical philosophy, even if they never been anywhere near Palestine, there would be a simple way to become the true "natives", and the Palestinians, the "colonial invaders": they just need to kick all of the Palestinians out, and wait.

With all of that said, that clearly doesn't mean that the Arabs who lived there for the past millennium and a half, are "invaders" with no connection to the land, and should just fuck off. And fortunately, only the tiniest minority of extremist Jews ever claimed they should. If the Arabs actually accepted the 1947 partition plan, as the Jews did, there wouldn't be a single Arab that would be displaced or lose any of his land, there wouldn't be any Nakbah, or any Israeli-Palestinian conflict. But instead, they believed they'd get more by war, and lost - and here we are.