Like the case of Rome before it, the Empire is bankrupting America. The true fiscal cost is upwards of $1.0 trillion per year (counting $200 billion for veterans and debt service for wars), but there is no way to pay for it.
That's because the 78-million strong Baby Boom is in the driver's seat of American politics. It plainly will not permit the $3 trillion per year retirement and health care entitlements-driven Welfare State to be curtailed.
The Trumpite/GOP has already sealed that deal by refusing to reform Social Security and Medicare and by proving to be utterly incapable of laying a glove politically on Obamacare/Medicaid. At the same time, boomers keep voting for the GOP's anti-tax allergy, thereby refusing to tax themselves to close Washington's yawning deficits.
More importantly, the generation which marched on the Pentagon in 1968 against the insanity and barbarism of LBJ's Vietnam War has long since abandoned the cause of peace. So doing, boomers have acquiesced in the final ascendancy of the Warfare State, which grew like topsy once the US became the world's sole superpower after the Soviet Union slithered off the pages of history in 1991.