On page 76 of the biography I refer to Cliff’s 1946 article “A New British Provocation in Palestine” [Fourth International, September 1946]:

He stressed that neither the Zionists nor the Arab leaders such as the Mufti, who had supported the Nazis, and the “clerical‑fascist” Moslem Brotherhood, could be consistent opponents of imperialism.

While this is a fair summary of Cliff’s 19456 position [the full article, with a substantial analysis of the Moslem Brotherhood, can be read at http://www.marxists.org/archive/cliff/works/1946/07/provocation.htm], I am grateful to Christian Hogsbjerg for pointing out that  both the Muslim Brotherhood and Cliff’s analysis evolved in subsequent years.  It seems highly likely that Cliff would have agreed with the argument developed in Chris Harman’s  1994 article [later pamphlet] “The Prophet and the Proletariat” – certainly I know of no evidence that Cliff ever expressed any disagreement with it.

In this article [available at https://www.marxists.org/archive/harman/1994/xx/islam.htm] Harman draws on Cliff’s theory of Deflected Permanent Revolution. He outlines the evolution of the Muslim Brotherhood:

In Egypt the Islamist movement first developed some 65 years ago, when Hassan al-Banna formed the Muslim Brotherhood. It grew in the 1930s and 1940s as disillusionment set in with the failure of the secular nationalist party, the Wafd, to challenge British domination of the country. The base of the movement consisted mainly of civil servants and students, and it was one of the major forces in the university protests of the late 1940s and early 1950s. But it spread out to involve some urban labourers and peasants, with a membership estimated to have peaked at half a million. In building the movement Banna was quite willing to collaborate with certain figures close to the Egyptian monarchy, and the right wing of the Wafd looked on the Brotherhood as a counter to communist influence among workers and students.

But the Brotherhood could only compete with the communists for the support of the impoverished middle classes – and via them to sections of the urban poor – because its religious language concealed a commitment to reform which went further than its right wing allies wished. Its objectives were “ultimately incompatible with the perpetuation of the political, economic and social status quo to which the ruling groups were dedicated”. This ensured “the liaison between the Muslim Brotherhood and the conservative rulers would be both unstable and tenuous”.

The Brotherhood was virtually destroyed once a new military regime around Abdul Nasser had concentrated full power into its hands in the early 1950s. Six of the Brotherhood’s leaders were hanged in December 1954 and thousands of its members thrown into concentration camps. An attempt to revive the movement in the mid-1960s led to still more executions, but then, after Nasser’s death, his successors Sadat and Mubarak allowed it to lead a semi-legal existence – provided it avoided any head on confrontation with the regime. The leadership of what is sometimes called the “Neo-Islamic Brotherhood” has been willing to accept these restraints, following a relatively “moderate” and “reconciliatory” approach, getting large sums of money from members who were exiled to Saudi Arabia in the 1950s and prospered from the oil boom. This has enabled the Brothers to provide “an alternative model of a Muslim state” with “their banks, social services, educational services and … their mosques”.

…..The same contradictions run right through Islamism in Egypt today [1994 IB]. The reconstituted Muslim Brotherhood began operating semi-legally around the magazine al-Dawa in the late 1960s, turning its back on any notion of overthrowing the Egyptian regime. Instead it set its goal as reform of Egyptian society along Islamic lines by pressure from within. The task, as the supreme guide of the Brotherhood had put it in a book written from prison, was to be “preachers, not judges”. This meant, in practice, adopting a “reformist Islamist” orientation, seeking an accommodation with the Sadat regime. In return the regime used the Islamists to deal with those it regarded, at the time, as its main enemies – the left: “The regime treated the reformist wing of the Islamist movements – grouped around the monthly magazine al-Dawa and on the university campuses by the Islamic Associations – with benevolence, as the Islamicists purged the universities of anything that smelled of Nasserism or Communism”.

…..Meanwhile, the Muslim Brotherhood has continued to behave like a loyal opposition, negotiating with the regime over the gradual introduction of the sharia into the state legal code and holding back from protests at the repression.

….. In Egypt the present day Muslim Brotherhood is based on a policy of reform directed at the state. It attempts to work within existing society building up its strength so as to become a legal opposition, with MPs, a press of its own, control over various middle class professional organisations and influence over wider sections of the population through the mosques and the Islamic charities. It also tends to stress the fight to impose Islamic piety through campaigning for the existing regime to incorporate the sharia into the legal code.