When leaders get a lot of criticism it is often because people have the impression that they don't know what they is doing. That is my impression of Obama's foreign policy too.
The Far East
The Far East is probably the best example. It is well known that East Asians are very sensitive to loss of face. So the classical saying of "talk softly but carry a big stick" makes here extra sense. A good starting point when reacting to Chinese transgressions might be: what would we do if Israel did this?
Instead we saw a very noisy "pivot" to the East. This amounted to a public declaration that the US is now in a low level state of cold war with China. Very few troops were actually moved to the Far East, but the damage to the relations with China was done.
All this comes from a misguided look at foreign policy that constantly looks for the next threat to US dominance. That country is then treated as an enemy. It would be much more fruitful to aim for a role for the US as world leader. The US could have transferred troops to East Asia without much noise - using natural disasters and other incidents as convenient excuses. The end result would still have been a larger US presence and that would still have led people to pay more attention to what the US was saying.
Obama's recent Asia trip that very explicitly left out China was another example. Such an open declaration of conflict with China demanded a reaction from China and that we saw in the form of the employment of a drilling vessel to Vietnamese waters. The Chinese very cleverly managed to expose Obama as a phony who makes nice promises but can't deliver.
Obama doesn't understand this kind of subtle diplomacy. Take the case when the Chinese unilaterally expanded their Air Defense Identification Zone (ADIZ). Obama made a very noisy public declaration against it, sent a few planes through it and then basically started to respect it. His predecessors would have done that differently. The would have condemned the declaration, but only softly, so as not to cause their adversary too much loss of face when it retreated. They would know that the louder they condemned the zone, the harder they it would make for the other side to retreat. Yet they would have been very consistent in not respecting the zone.
Or take the gradual expansion of the Chinese occupation of islands claimed by the Philippines. The US has a lot of ways to react. It can expand some bases in South East Asia. It can provide some advanced weapons or training to Taiwan or other countries in the region. It can take some measures obstructing Chinese exports to the US. Etc. Such moves don't need to be published at all: the Chinese leaders will know and connect the dots. And if they occasionally don't there are diplomats to help them discretely.
If such indirect retaliation might not help there could be a next level of escalation. Again to be done discretely.
This is how soft power works. Unfortunately Obama is a former community organizer. That is: he organized people with little power against people with much more power. In such a position there is no soft power and naming and shaming is a major part of the strategy.
Unfortunately the US doesn't understand sanctions. They make a big show of them. And then they are surprised that the other side resists in order not to look weak and not to raise the impression that they are vulnerable to blackmail (sanctions are a form of blackmail).
Wars of choice
Iraq was a war of choice. But so are Libya, Syria and Ukraine now. Obama believes that he is smart for keeping U.S. soldiers out so that he can't be blamed for dead soldiers. But for the local population there is hardly a difference.
Take Syria. Obama believes that he is smart for keeping Russia, Iran and Hezbollah forever bleeding on Syria's battle fields. Very probably he got the idea from his mentor Brzezinski who did something similar with Afghanistan in 1979. But in the end the US paid for that act of cynicism with 9/11. Most people - both inside and outside the US - consider the lack of respect for human life that this strategy shows disgusting and immoral.
Obama's "red line" on Syria's chemical arms was another example of ignoring "talk softly but carry a big stick". A superpower like the US shouldn't make big statements like this. When chemical arms are used it should send in investigators and slowly escalate the issue - without committing itself to any course of action. Unfortunately it looks like Obama never cared about the issue: he just wanted a pretext for intervention.
Since the testimony of Kubic we know that the war in Libya was not necessary and that openings from Gaddafi's side to negotiate about his departure were deliberately ignored by the Obama administration.
After Gaddafi had been driven out America's main activity in Libya seems to have been its failed Benghazi mission that is more and more rumored to have been an operation buy weapons that had been given to Libyans Islamists and to give transport them to Syria. In the mean time there was little attention for turning Libya into a working state.
Ukraine first saw a US sponsored "revolution" and now we see the US doing its best to keep the conflict going by obstructing all dialogue. It looks like Obama believes it is in the American interest to create as much hostility as possible between Ukraine and Russia.
Obama is listing the withdrawal from Iraq and the partial withdrawal from Afghanistan as achievements. But withdrawal was a logical consequence when there was nothing more to get for the neocons. Given that there were to be withdrawals it is hard to claim that Obama has done them particularly well.
The negotiations with Iran are about the only spot of light. But they are constantly under fire from interest groups.
NSA and CIA
Obama's obsession with sneaky methods is becoming proverbial. Whether NSA snooping, color revolutions, CIA waterboarding or killing by drones, intervening under false pretexts: he is in favor.
He seems to miss the harmful effects of these policies. Internally they have the effect of driving out all the honest people. What remains are organizations dominated by opportunists who can't be trusted to defend America's interests. Externally they destroy the image of leadership and responsibility that the US once had and replace it with an image of a bully on steroids.
Contact with reality has been lost
The State Department is in a sorry state. It has been underfunded for decades and as a consequence it has often had to play second fiddle to the Department of Defense. Things became even worse under Bush Jr when many senior diplomats left in disgust because they disliked being forced to defend Bush's undefendable aggressive foreign policy. Obama brought in the amateurs with his unprecedented level of appointments of campaign contributors to diplomatic posts.
Without a functioning national bureaucracy that keeps track of the issues involved and best practices US foreign policy has become a free for all feast. Lobbying groups fund "research" institutes that publish quasi-scientific articles promoting the policies they want. Loudmouth politicians like McCain profile themselves as warriors by anointing whoever they want as an enemy.
The invasion in Iraq was a good example. Iraq was not an enemy of the U.S.. No American interests were involved. Instead the main motives for the Iraq invasion were outside the area of America's national interests: Bush taking "revenge" for his father, greedy oil and defense companies and a climate where people feel empty when the U.S. is not involved in some foreign military adventure.
The lack of attention to the rebuilding of Libya and Iraq fits in this pattern. Although such attention would be crucial to turn those countries US friendly - what the interventionists saw as their goal - it doesn't get any attention from the US administration as it no political points can be scored inside the US with such unsexy work.
Kerry is very much a product of this system. He doesn't see the world as a group of collaborating countries. He doesn't have a vision of how the world should work. Instead he goes around the world trying to bully every country to support what is the newest fashion in U.S. foreign policy.
From the perspective of the common American this doesn't make sense. Their prosperity would be much better served by a stable world shaped and supported by a capable U.S. diplomacy.