Considering the Palestinian conflict yields a still modern issue with strong ties to Pan Arabism.
Some background:
In the aftermath of the conflicts between Jewish and Palestinian inhabitants before British withdraw, and of the 48' war between Israel and surrounding Arab states, the Pan Arab world view was on strong display and about to be transformed. The Arabian leaders, despite efforts to cooperate, were largely suspicious of each other. This was especially apparent through their mutual distrust of Trans-Jordan, which was positioning itself to control the West Bank, while the others were trying to undermine this goal. In fact this war had much to do with the shaping of Pan Arabism. An edifying example is that Nasser himself was surrounded with other fellow Egyptian officers in Palestine. Upon their return to Egypt, coups followed. These officers played critical roles in subsequent Egyptian politics.
Intellectuals like Zurayk and Alami stressed the need for Arab unity following the war. Alami even used terms like an 'Arab Prussia'. Their call was for an internal revolution of Arab countries, transforming deeply entrenched ideas and norms set by years of imperial control over the countries. Only following such a 'renaissance' would the Arabs be able to reposition themselves in the world and handle the consequences of the 48' war.
The consequences of this war and subsequent events are of crucial relevance still today. The failure of Pan Arabism to control the refugee crisis from Palestine and relocate them has caused much strife and pain both internally in countries like Jordan and Lebanon, and through war atrocities, as demonstrated in the 82' Lebanon war between Hezbollah and Israel. The refugee issue, and the claimed right of return is a major political drive in Israeli and Palestinian politics.
Moreover, the Palestinian issue is still being used today by Arab governments to flare up their populations around the idea of Arab unity and distract from internal corruption and inequality.
Major source; The Arabs, A History, by Eugene Rogan.