Re the Israel-Palestinian Issue, Melanie Phillips Calls for a Liberal Dose of Reality

Melanie Phillips (tongue lodged at least partially in cheek?) thinks there's a cause that those of a "progressive" bent should embrace--the cause of anti-Palestinian colonialism. Her reasoning? "Progressives," she says,

are against racism. They are against colonialism. They are against ethnic cleansing. They are against police states. And they are against antisemitism.

So there is a political agenda that is surely tailor-made for Western liberals and left-wingers to shun and condemn as an utter negation of all they hold dear. 

The goal of the Palestinians is the colonial conquest of another people’s country. That country is the State of Israel, the homeland of the Jewish people whose unique connection goes back to antiquity...

Problem is, it's going to be awfully hard for "progressives" to make that leap when it goes against everything they've been taught and have held dear for lo, these many decades.

What makes Ms. Phillips believe that, given their worldview and the leftist self-loathing that's integral to it, "progressives" are suddenly capable of grasping--or even grappling with--the truth?