He appears to have been caught because the summary is so much better written than anything Žižek has ever managed to write, and thus stood out like a sore thumb.
Sailer (Deogolwulf, who first caught the plagiarism, is comment 22). There are some excellent critiques of - and a lot of praise for - MacDonald in the comments.
This comment is great fun:
"MacDonald’s thesis would be well served by a deeper analysis of Israel. As things stand, Israel is a project to integrate various largely unrelated Jewish peoples, most of whom are profoundly cognitively inferior to the dominant European Ashkenazi Jews, who now represent well under half of the Jewish population of Israel, and under 40% of the Israeli population overall. As an ethno-nationalistic Ashkenazi Jew, . . . "
The comment by Guillaume Durocher is worth thinking about.