Washington( CNN) The fate of Donald Trump's presidency may hinge on what he does next.

His failure to convert the core campaign promise of repealing and replacing Obamacare — even with a GOP monopoly on power in Washington — has left the White House reeling.

Trump and his advisers must now regroup and try to figure out how to avoid another legislative debacle on their next big issue, taxation reform. They will do so knowing that a second failure could throttle his presidency.

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