Fighting wars, big tax cuts and economic stimulus packages have all added to the debt burden
Raising the debt limit is the only way out for the USA in December 2017. If not, the government has to shut down in December as there's no money to be spent anymore.
How will the government get the money for its spending? Look like printing money is the only way out for Trump as he wants to implement fiscal spending to boost the economy but still want tax cuts simultaneously. Increasing the money supply will definitely devalue the currency. OK, we have the outcome for the USD in the future now.