One of the major reasons that Hamas remains in power despite the international "boycott" is because the boycott is a joke.
The infrastructure of Gaza is paid for by the PA, which gets its money from the same governments that pretend to not fund Hamas. Hamas is then free to do whatever it wants without worrying about people getting too upset.
A new study by the Palestinian Economic Council for Development and Reconstruction (not yet available in English) shows some stunning numbers:
The PA employs 150,870 staff, of whom 78,000 employees are in the Gaza Strip, including 31,350 military personnel and 45,650 civilian staff. So more than half of the paid employees of the PA "work" in Gaza, which has roughly one third the population. Not only that, but the Gazans get paid more: right now 68.5% of the PA wages get paid to Gaza employees.
335 million shekels flow from the PA to Gaza every month, and Hamas gains tens of millions more from its own taxes - none of which go back to the PA. Outside donations give Hamas another 77 million shekels a month.
PECDAR goes on to estimate that the PA pays some $368 million dollars annually to employees in Gaza who do, literally, nothing.
When Israel still occupied Gaza, Gaza was responsible for 30% of the PA's GDP - because of the jobs that the evil Zionists provided to the Gazans. Now the number is virtually zero. Yet the percentage that the PA spends in Gaza has increased, from less than 50% in 2005 to the 68.5% now.
The reason Hamas prospers is because the world, via the PA, is funding it. Hamas is free to concentrate on weapons and smuggling because it doesn't have to worry about schools and water and all the normal civic responsibilities that every government has.
Is there any wonder that Arab nations are now balking at funding the PA?