The section header preceding Joshua 10:29 reads "Joshua's Conquest of Southern Palestine". Similarly, the heading before Joshua 11:1 carries the heading "Northern Palestine Taken". Both printed and digital versions of the NASB use these headers.
Other translations such as the ESV, NKJV, CSB, and many others, refer to this same area as "The Northern Region of Canaan" or some variation of that.
Dr. Michael Brown, a conservative radio host, author, and professor, put it plainly, "The problem, of course, is that 'Palestine' did not exist at that time, and if a place name was needed, then 'Canaan' would have sufficed."
The section headers are subject to translators, so it's not so big of a deal as it would be if they'd used Palestine in the translation of the original text. But Brown argues, "They can become as fixed as the translation itself".
"I'm not implying anything sinister, since the NASB renders one key passage in a way that I would say is not only accurate but also refuted a supersessionist interpretation," Brown clarifies. If there were anti-Israel bias, it would've shown in specific passages of the New Testament, but it didn't.
So, again, this professor, who has himself dabbled in Bible translation, poses the question: Why use "Palestine" in the section header?
"When it comes to Bible history, especially Old Testament history, there is no such entity known as 'Palestine,' and there is absolutely no justification for its presence in the section headings of the NASB (or, any other Bible for that matter) when talking about biblical events," Brown rants.
This conservative Christian leader suggests the most extreme argument to answer the question, saying, "To do so is to agree with the anti-Israel talking points of Palestinian activists, who also claim that the ancient Israelites engaged in the ethnic cleansing of Palestine (those evil Israelis are doing it again today!) and that Jesus was 'a Palestinian messenger.'"
Michael Brown, who is a known proponent of Messianic Judaism, says he looks forward to those responsible for the translation error in the NASB rectifying the mistake.
Brown also posted an update on the bottom of the article to say that he's been informed that the 2019 revision of the NASB is already planning to replace "Palestine" with "Canaan" in the noted passages.