Could Trump Take the Economy Down With Him? & Can Presidents "Make or Break" a Market?

The United States 2020 Presidential election has been called by pretty much every organization that covers the event in any capacity and while the final decision is not made until the special club that is the electoral college has presented its final decision, it’s apparent that Joe Biden will be the next president of the united states.  This is the first time in almost 3 decades that an incumbent president has been voted out before serving a second term and it has come in the midst of national and global catastrophes galore.  To add fuel to a fire that threatens to ignite the global economy, the outgoing president has been vehemently challenging the results which is casting doubt over the smoothness of the transition, the continuation of much-needed government support, and the foundation of the nation’s systems in their entirety.  And this all begs the question, either unwittingly or maliciously, how much damage could a president do to the American economy, and by extension the global economy.  There are checks and balances in place to control the influence of any one man in the united states around things that were relevant when those checks and balances were been written. But it must be remembered economies back then depended a lot more on successful harvests, and a lot less on tweets.  Our modern economies are incredibly complex and incredibly fine-tuned, but complex fine-tuned things tend to be very easy to break, and the outcomes of throwing a proverbial spanner into the works could be just as devastating.  Thousands of people die when unemployment rises, and many more could lose access to healthcare, housing and livelihoods during even a minor period of economic turbulence. All of this is to say that a president waging war on an economy could be just as dangerous as waging war on a nation.  What kind of influence does a president directly have over an economy? Do they deserve the credit for things going well? And what could a president do to tank the economy if they really wanted to?