>>>> decreased tax revenues -> deficit
This is only partially true - IIRC, CBO estimates are about 24% of the Bush-era deficits were caused by tax cuts. The rest is spending increases and tax revenue falling short of previous expectations (i.e. would happen with or without tax cuts, and without tax cuts would probably be more severe as tax cuts were observed to decrease tax avoidance). The difference between 400bn and 1trln can not be explained by tax cuts.