disasters and military actions (anyone who doesn't budget for both nowadays is very shortsighted at best). Add on to this other areas of spending as required.
Now show ANY taxation plan that funds all of this. ANY plan.
If you haven't done BOTH of these, then you have absolutely NO idea whether this is "sustainable" or not.
This is the difference between politics and leadership. Politics plays for the next election, and wages the perpetual political campaign (we've been doing that now for 22 years or longer). Leadership faces the issues, generates the plans, and then follows through.