During his “State of the State” speech Tuesday, Gov. Arnold Schwarzenegger repeated his mantra about the “hidden tax” in Californians’ health insurance premiums.

The governor says we pay more for our coverage to compensate for care given to the state’s 4.8 million uninsured.

But the governor’s proposal to fix the problem —- universal coverage for everyone living in this “nation-state” —- may have much larger “hidden taxes.”

First, he assumes the federal government will be willing to pony up additional cash to pay for increased Medi-Cal payments to doctors and hospitals. Going by the optimistic outlook in the proposal, additional cost to the feds is $5.4 billion.

California politicians, including Schwarzenegger, have long lamented the federal government’s unwillingness to reimburse the state for emergency room care given to illegal immigrants. What makes him think Washington will want to kick in now? And if that happens, where will the money come from?

Schwarzenegger also assumes that businesses won’t drop their health plans and send their employees to the state. The governor wants to tax employers with more than 10 workers 4 percent of their payroll if they don’t already provide health insurance so the state can do it for them.

Four percent of payroll is significantly lower than what most businesses contribute to private plans. According to the U.S. Census Bureau, in 2003 American businesses spent between 6 percent and 9 percent of their payroll on health insurance. In California, that number is higher. Surely, many companies would rather spend just 4 percent on health benefits.

And how is that 4 percent tax going to pay for Californians using coverage offered by the state? Businesses can’t find insurance coverage that cheap, and more often private enterprise is much more efficient than government. We can safely bet that the state’s coverage is going to cost more than Schwarzenegger assumes, and we will all end up paying for it.

Schwarzenegger also proposed taxing doctors 2 percent of their earnings and hospitals 4 percent. These care providers are already dealing with the hassles of insurance companies and government mandates, and will likely pass that tax on to their patients and, in turn, insurance companies —- which will be forced to increase premiums. The “hidden tax” comes full circle.

The governor’s proposal to expand the Healthy Families program to cover the state’s 750,000 uninsured children is the only part of this plan that makes sense.

On paper, he shows the overall plan breaking even, but on closer inspection, Schwarzenegger’s numbers don’t add up.