Israel's enemies point to the defending border wall Israel built as a reason to label Israel an apartheid state. If that is a valid reason then the United States is also an apartheid state because of their wall on the Mexican border.
Everyone must agree it is the duty of a government, in this case Israel, to protect its citizens from Islamic fanatic suicide bombers. There are so many of these bombers who have, and are willing to, forfeit their lives in order to kill Jews and whoever (Christian ,Hindu, Muslim, etc.) happen to be in the area.
An apartheid state does not allow the segregated people citizenship nor equal rights such as voting or freedom of speech. One and a half million Arabs live in Israel; they constitute about 20% of the population. Every single one of them has the same exact rights as any other Israeli citizen -- and always have. They can vote, and they do. They can own property, businesses, and work alongside other Israelis, and they do. They can serve in the Israeli parliament, and they do. There are Arabs in the Israel government such as Masud Ghnaim, an Israeli Muslim politician, who is a member of the Knesset. Then you have Abdel Rahman Zuabi who took his seat in 1999 as the first Arab to sit on the Israeli Supreme Court. No way does this sound like an apartheid state.
So why are Palestinians who live in what they commonly refer to as the "occupied territories" treated differently? Because they're not citizens of Israel. They are governed by either the Palestinian Authority or Hamas. It is not Israel, but the Muslim dominated nations, that have confined Palestinian-Arab refugees to UN welfare in camps in Gaza, the West Bank, Lebanon, Syria and Jordan for generations. The only control Israel has over these people takes place when they want to enter Israel, because Israel has to weed out potential terrorists.