These career govt employees feed info to the pres, make recommendations, and fight for their interests. Even if a new pres wants to turn on a dime, Washington DC is a large ship that turns slowly.
Bingo. The old UK comedy "Yes Prime Minister" was a rather cutting illustration of this phenomenon at work.
What happens to someone when they become the prez? Enormous numbers of apparently experienced people begin telling you all kinds of secret things. They stress the importance of secrecy. They tell you about this plot or that plot. They say it's vital they get new powers and they not-so-subtly imply that if you don't help them Women And Children will DIE! And although it's left unstated you know perfectly well that if you don't give them what they want, you will see leaks in the press from anonymous officials that paint you as a prevaricator, as weak, as unconcerned for the lives of Patriotic Heroes And Their Women And Children.
The problem any US President has, and I daresay many other countries presidents, is that they are immediately submerged into a fantasy world woven from the agendas of the people around them mixed with their own pre-existing views, and those people are themselves also in a slightly less extreme form of a personal fantasy world and so on all the way down. A toxic brew of patriotism, belief in American exceptionalism, militarism and most of all pervasive classification means that it's impossible for a prez to penetrate the fog of misinformation that surrounds them. They can be manipulated into believing nearly anything because it would take an incredibly strong willed personality to say directly to the senior bureaucrats feeding them classified intelligence, "I think you are bullshitting me and I am going to personally audit your shit and prosecute you if you're lying to me".
Obama is very much NOT a strong willed personality. He sees himself primarily as a reasonable man who finds compromise between different factions. This makes him easily manipulated: all it takes is for people who agree to present him two apparently opposed positions - one extreme and one very extreme - and Obama will reliably pick something that is quite extreme. And the officials around him know that.
In hindsight it should have been obvious. Obama has no real track record of achievement in politics. He supported no particularly controversial positions, or showed any particularly clear thinking. Compared to Bush he seemed like a genius of course but Bush was a fucking man child, so that wasn't hard.
For that reason, Rand Paul fans might be disappointed if he won. I don't expect he would be able to accomplish as much change as people would like.
Almost certainly not. But it looks like Rand Paul is made of stronger stuff than Obama. Paul consistently argues for positions that piss off most of his party. He seems able to come to conclusions about things himself regardless of what other people believe. He seems to have fairly strong principles. He doesn't come across as the sort of wishy-washy people person that Obama is. If there's any US politician that actually might tell the people in his secret briefings "stop bullshitting me or I fire you", it's probably Rand Paul.