If you walk by a dime on the street and don't pick it up, you didn't just spend 10 cents.
True, but if you're looking for any form of income, those 10 cents are a lost opportunity cost, and sometimes, all you need is 10 cents to achieve something. Instead all you're left with is the question of what you could have been able to achieve had you picked up those 10 cents. It's income you could have collected, but decided to forgo. When the final numbers come in, they don't account in any form (not a loss, but not a gain either).
Now, I don't disagree that the tax cuts should have been packaged with spending cuts, but I don't consider it some indictment of Paul, who's record clearly demonstrates a consistent commitment to lower taxes and govt. spending/waste, as a hypocrite. While the rest of the Republicans have abandoned fiscal reality in now completely ignoring the spending side of the equation, he's doggedly continued to try and address lowering expenditures.
Again, Rand Paul's record only shows that he's all bark and no bite. Had he defected from the tax cuts vote, Republicans still had one more vote to play with (Doug Jones had not been sworn in so Luther Strange still provided the 52nd vote). In the end, though, he choked and bowed to the will of the party.
It's the least economically harmful option...a growth-friendly tax structure while pulling back spending by more than any potential loss in revenue. Though this one won't always be an option if the debt can is kicked down the road far enough.
It still doesn't address the fact that you have negative cash flow. It may be growing slower, but it's growing nonetheless. I bring the example of the paycheck: what you think is "least economically harmful" is having a lot of debt and bad spending habits, but cutting your paycheck and still keeping spending barely changed. Still have more money going out than in (well, now you have WAY less), and the elephant in the room still hasn't been addressed (the debt).
You said it yourself here. There's more downside to this approach...lower government spending plus an increased tax burden makes for a much tougher economic environment...although there will come a tipping point (maybe we're already there) where tax increases and spending cuts will be the only option.
If debt is SUCH a high priority like Rand Paul makes it sound like, this is the only alternative, especially if drops in the bucket like the 9/11 Fund are so large that they'll worsen the debt far more than tax cuts or defense spending.