Cramer pointed to Disney, which he said would see an immediate boost to profitability if the tax rate came down. However, that beckoned the question of what it would do with the extra money.
"Like so many companies, Disney's already awash in cash. It's not like they need more capital to expand. In fact, just today we heard that the company may have laid off as many as 100 people at ESPN — I don't expect a corporate tax cut will get them re-hired," Cramer said.
Instead, the entertainment giant might increase its stock buyback or raise its dividend, a boon to investors but not the federal government, which hopes the cuts will in part fuel job creation.
Disney could make more movies or open more theme parks, thereby hiring more people, but as it has been buying back shares aggressively over the last five years, the latter seems more likely.
"There's a perception that if companies use this money to buy back stocks or boost their dividends, the money's basically wasted because it doesn't create jobs. But it certainly would create more wealth for you, the shareholders," Cramer said.
A 15 percent effective tax rate could also encourage foreign companies to do more business stateside, an additional benefit to the U.S. economy.
"Plus, there are a lot of investors on the sidelines waiting for this market to come down to a more reasonable price," Cramer added. "What happens if so many companies are suddenly making more money because they have a lower tax rate? I bet it would force billions and billions of dollars into the stock market from the sidelines in a virtuous circle of wealth creation."
However, a corporate tax cut would dramatically widen the deficit, and President Donald Trump's repatriation initiative would only provide a one-off solution, Cramer said.
Even more daunting are the Senate Democrats, who are likely to filibuster any Republican proposal.
And budget reconciliation, which would allow a Republican majority to bypass Democratic opposition, might be a dead end according to tax experts who say the only way to use it would be to make the cuts temporary, with a two-year expiration date.
"A two-year tax cut? That's not going to change much of anything. [It's] kind of like a tax holiday — maybe you get some one-off special dividends like the one that Costco just gave you, but that's it," Cramer said.
The personal tax reform side of the equation is even more complex. The dividend and capital gains taxes would go down to 20 percent, making stocks attractive, but the rest of the plan is controversial and subject to criticism from House and Senate Republicans with their own plans.
"But let's cut to the chase. Should you buy stocks in anticipation of the huge tax cut? The answer is point blank: no. The truth is we have no idea what will pass, and I seriously doubt this current plan can make it through Congress," the "Mad Money" host said.
For the moment, Cramer still recommends staying the course. And, while investors should keep tax cuts in mind as a potential blessing on their portfolios, don't count on them too heavily.
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