Latency and network availability
Latency and network availability are the biggest issue for US businesses. As far as Internet speeds go and infrastructure reliability in general the US is falling more and more behind other nations, including those who are not economic power houses. Here most companies spend money on battery backups for each work station, hard pressed to find that in Europe.
What does all this fancy cloud stuff do us good when the network is wonky and the power is destined to go out on a hot day, a cold day, a rainy day, or when some truck driver makes a mistake and knocks a pole over. Top shelf cloud services with B grade infrastructure are not helping anyone.