Snowden is charged with theft, not treason. He knew that his actions would result in a closed-door trial without the possibility of a public interest defense. He signed a large stack of non-disclosure agreements that spelled out the consequences.
Whatever the perception may have been after 2013, it still is an open question as to Snowden's intent. His first stop in HK, along with his disclosure of US cyber activities against Chinese servers, indicated possible intent to defect to an adversarial state. His next stop was to Moscow, after he may have visited Russian handlers while still in HK. His Moscow voyage did occur a day after his passport was cancelled. He was almost certainly advised, via Assange's camp, that Russia would be a suitable destination. This almost certainly factored into his decision to seek a flight that stopped in Moscow. At best, this was likely a fall-back strategy as it was clear to him and his supporters that hiding in a South American country would not provide the same degree of protection afforded by Russia.
It is difficult to take Snowden's word on his account regarding motivations and (supposed lack of) conspirations. His actions took place during the Magnitsky debacle, including his initial contact to Greenwald.
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Look at his agenda now. He speaks as if he's on USA's side. Yet he admits he no longer represents the USA, speaks out against the USA, and chooses to avoid facing justice. Defection is not a difficult working conclusion to reach at this point, possibly pre-meditated. He certainly had the opsec to cover his tracks while still stateside, having been trained by the CIA.
Snowden, you were silent when Putin declared war on Ukraine in 2014 by annexing Crimea, and you are voicing support for the Kremlin. From my point of view, you are, at this point, a defector to the Russian Federation. You will cowardly avoid facing justice. Your actions have had vast and largely immeasurable consequences to the detriment of western national security -- all of which will be revealed behind closed doors if you choose to return and face the charges against you.