With the removal of the Egyptian president, Mohammed Morsi, the future of the Muslim Brotherhood, and Islamism in general, is undoubtedly at a turning point. The question is typically being cast as a binary: is this "the beginning of the end" or "the end of the beginning" for the Islamist movement? Even if, in the final analysis, this proves a misleading question, it nonetheless articulates a precise and instructive framework for what is at stake.
Many observers have no doubt that this is the beginning of the end of the Islamist movement, at least as it has been traditionally structured and as a dominant ideology in the Arab states. According to these observers, if the oldest Muslim Brotherhood party cannot maintain popular legitimacy in Egypt after only one year in office, then the ideology itself simply isn't a practicable model for governance anywhere.
Sunni Islamists will invariably fail in power because Islam is a religion and not an actual political ideology. Islamism doesn't have the intellectual heft, breadth or depth to suggest any answers to most policy questions. It essentially boils down to a set of religiously conservative social attitudes. It only takes a short while in office to reveal that.
Moreover, the very qualities that made the Brotherhood so effective as an opposition group - secrecy, discipline, streamlined hierarchy and a paranoid suspicion of all outsiders - proved crippling in office. They never made and, this argument holds, can never make the transition from an oppositional party and secret society to an open, effective and governing movement capable of consultation, conciliation and compromise. Mr Morsi's downfall therefore marks the beginning of the end of a project that was never actually realisable.
Others retort that this perspective ignores the undeniable depth, strength and resilience of the Brotherhood. This is a heavy blow and setback but, they suggest, it represents the end of the beginning for the region's Islamists. Islamists have learnt from the previous mistakes and will again following Mr Morsi's downfall. The group remains well positioned for any future elections, because of both their strong constituency and the continuing fragmentation of their electoral opposition.
It's not surprising that the Brotherhood would experience hiccups during their first time in office but they are not going to go away. Instead, they will regroup and return strongly to the fray, possibly more powerful and effective. And, the argument continues, both Egyptian and regional Islamists have already proven capable of learning lessons and adapting.
There's an element of truth to both positions. Political Islam is never going to go away in Muslim-majority societies. The only questions are: what will it look like, and how effective and popular will it be? But the failure of Egypt's Brotherhood to maintain popular legitimacy and power bodes ill for the future of traditional Sunni Arab Islamism and the prospects of producing effective, legitimate governance.
The most likely long-term effect of this Islamist crisis is a gradually, perhaps rapidly, developing split within the movement between those who stick to traditional approaches and a latent - or, as sociologist Asef Bayat would argue, already emerging - post-Islamist trend. There is significant evidence that such an ideological split is already underway, mere days after Mr Morsi's downfall, given open disputes among Islamists throughout the region about the extent to which the Brotherhood, at least partly, brought this upon itself.
An emergent post-Islamist orientation would retain the essential Islamist trait of reclaiming the centrality of Muslim identity. But it would no longer misread Islam as a political ideology. It would not look for policy prescriptions in faith and apply "Islam has the answers" to the detailed, technical problems of governance. Instead, this emerging or potential post-Islamist trend returns Islam to the realm of identity and values, rather than law and policy.
Mahmoud Jibril, the leader of the Libyan National Forces Alliance, which thrashed Islamists in the party section of the Libyan legislative election, might be seen as an exemplar of where a post-Islamist political stance might situate itself vis-à-vis religion and society. Mr Jibril never allowed Islamists to outbid him on Muslim piety, insisting he was as devout and observant as anyone else. But he argued he was more patriotic than the Islamists, who were aligned with both a regional movement that does not put Libya first, and foreign powers, specifically Qatar. And he strongly made the case that Islam was too holy to be sullied with the profane world of politics. If the Libyan election was any indication, this hybrid, experimental and perhaps prototypically post-Islamist stance resonated strongly with the public.
However, such new trends might - at least initially and especially if they primarily emerge out of the existing Islamist movements - retain a greater emphasis on social conservatism than Mr Jibril's non-Islamist or post-Islamist rhetoric.
It remains to be seen how viable a hybrid of Islamic identity with nationalist sentiments and social justice concerns, and a due regard for the rights of individuals, women and minorities can be in the present Arab political environment. And it's not clear how unified or coherent such a movement would prove. But the potential appeal of a post-Islamist brand of politics in the Arab world seems clear.
If Mr Morsi's downfall marks the beginning of the end for traditional Islamism as a failed experiment, even by forcing its own adherents to learn and adapt, then much of the Arab political space it has occupied may give way to precisely such a post-Islamist movement.
Hussein Ibish is a senior fellow at the American Task Force on Palestine, a columnist for Now Media and blogs at www.ibishblog.com
On Twitter: @Ibishblog