If anybody thinks are country is better off today than it was in 2008, then you're probably on drugs or just don't care. Barack Obama has doubled our national debt, he has racially divided this country with his "identity politics", and there have been countless terror attacks in our country as a result of Obama's failure to protect our nation from a threat that he let grow into what it is today (ISIS/ISIL).
Although I agree that the quality of the US has gone down, I don't think that Obama is the cause for our problems. Laws and rules created centuries ago are now being misinterpreted and abused. People are spending much more than they are capable of spending and blaming their loss on the President. Obama did definitely improve relations with foreign countries, and he did the right thing when he chose to take in immigrants who were at risk of getting killed or forced to receive inhumane punishments. However, the apparent "right to bear arms" found in the Second Amendment is being shouted across the country to defend one's ownership of guns, even after a large number of shootings in public settings
While I have great respect for the President, I think his policies, foreign and national, lack the force of his predecessors. His foreign policy has been too lackadaisical, if not outright abysmal. The Medicare reform bill is something that is yet to gain any sense of popularity -- although, it is slowly gaining ground. If a democrat is not elected President this fall, there's a good chance that the changes brought about by the Medicare bill (Obamacare) could be reversed.
More importantly, most Presidents, have managed, at some point during their Presidency, to bring together a unified Congress albeit for a limited amount of time, and even on limited issues. President Obama will never have that feather in his cap. His approach, for some unfathomable reason, has been a sort of "divide and rule" policy.