This is a complete false premise. If the UAE company buys these ports....they will not be "secured" by Arabs. They will be secured by exactly the same people that are securing them now. Do you see "British" security officials at our ports now doing the majority of security? - Of course not.
Really, so if the UAE company buys these ports, they will not be responsible for the security of them? I guess "buying" doesn't really signify the interest in property that I thought it did. Who knew? Maybe Clinton was right about the meaning of "is." /sarc
But, while true, it's somewhat beside the point. The manager of the ports can easily make sure that certain containers are not inspected, and in fact maybe never show up on the paperwork. All sorts of ways an infiltrator, a sleeper from the UAE for example, could create mischief at a port. This was something of a problem with the Brits, since they have so many residents and citizens who are ethnically and religiously on the wrong side of this divide.