The debt grew substantially UNDER Obama's terms in office, but not all of it was directly attributable to Obama's actions and policies.
In fact, it's possible to look up specifically what WAS directly attributable to his actions and policies, just as with any administration. National debt is a long term thing, and its accumulation is from long term actions, some of which specifically and EVEN INTENTIONALLY are designed to outlive the two terms of a presidency.
In POINT of fact, some actions from an administration AND from a session of Congress even STATE that their actions will continue "beyond the presidency" and some laws passed BY CONGRESS are dubbed "PERMANENT", such as the recent corporate tax cuts.
Looking at the national debt through the ideological equivalent of an empty cardboard toilet paper tube is, in a word:
MYOPIC.
And it brings with it, its very OWN sort of SLANT.
Oh and lastly, SOME national debt is actually a very good thing, and extremely important, because SOME national debt is actually a valuable financial instrument.
I would challenge you to think about what would happen if every penny of the entire 20 trillion dollars of the national debt were to be PAID IN FULL TOMORROW.