Yeah, but the vast majority of military expenditures were agricultural in nature. Take artillery. The buggers cost a fortune to cast. The powder was expensive. And you needed a lot of trained soldiers to operate them, but over the life the piece (which might be 100 years) the biggest cost was ... the horses/oxen you need to move the thing. Likewise, the single biggest cost for your artillerymen was their food. For just about any expenditure in the EU era, food for the workers/soldiers is just about always the biggest expense.
And what is the bulk of GDP in this era? Subsistence farming. As most of this is not monetized, it never sees the light of day in the French treasury (this is why trade, which was a tiny amount of world output was so important - you could tax it easily). The vast, vast bulk of the French economy pre 1800 is geared to agriculture and there were millions of Frenchmen trying to maximize their agricultural output. Even the nobility, who might not work the land directly, were deeply involved with the rents from their lands which were wholly dependent on agriculture. Remember the proximate cause of the French Revolution is the king needing money to pay down debts and the only viable means to do so being more tax in a largely agricultural society where higher taxes meant hunger.
The entire world's disposable income in pre-Agricultural Revolution days is dwarfed by that of single states post-Revolution. And, oddly enough, autocratic rulers have typically been unable to implement them. All of the early states - the Netherlands, GB, France, USA, Switzerland, Germany, Argentina, etc. were those that had specific limitations on executive powers. Those states with the greatest degree of absolutism - Russia, the OE, China, Spain, Persia, etc. were among the worst. Quite tellingly when the USSR opted to force through an agricultural revolution - perhaps the biggest confluence of pre-existing technology and absolutist control - it failed abysmally. Likewise, the attempted modernization of Chinese agriculture was a complete flop until Deng Xiaopeng moved to a less autocratic model. Globe spanning autocracies are actually likely to be among the least viable sort of societies to rapidly modernize agriculture and hence industry and science.
