Since the end of WWII, the US has overthrown at least four democratic governments (more than China) and funded numerous authoritarian governments that were/are US-aligned. To much of the world outside the north Atlantic states the "democratic order" is viewed a lot more cynically. Especially ask someone from Latin America what they think of this.
Saudi Arabia was the key force that reverted the democratization of Bahrain and in general is a block for democratization in the Arabian Peninsula. That you don't think they are a threat to democracy belies what your "democratic order" really is: US hegemony.
Kinetically, no. Strategically they can and do mess with America's blood pressure by twiddling the valve on their oil output. China fields a lot of conventional military force though I have my doubts about their desire or ability to project it farther than Taiwan.