If the Obama administration is trying to scare big banks straight with its tax proposal, it seems unlikely to work.

Industry watchers' description of the plan to charge a 15-basis-point fee on net liabilities ranged from an annoying, yet manageable, cost to a misguided policy.

Besides recouping the cost of rescuing the industry, the tax is intended to discourage "excessive" size and risk-taking, administration officials said.

But the tax would do little to curb behaviors that policymakers want to keep in check because it would be less onerous than many other costs and challenges already faced by the industry. Early calculations by several analysts say large companies such as Bank of America Corp. and JPMorgan Chase & Co. would pay about $1.5 billion per year.

"This is a marginal disincentive for the use of leverage," said Sean Ryan, an analyst at Wisco Research. "I am convinced that people in Washington don't want to change how Wall Street works but they want a piece of the action. This accomplishes that."

Others were more blunt.

"The new big-bank tax is just like charging a nickel sin tax on a half-gallon of cheap liquor — it may make moralists feel good, but it doesn't do much to stop bad behavior," said Karen Shaw Petrou, managing director of Federal Financial Analytics Inc. "A penalty tax for large financial firms does nothing to address too big to fail or root out the real causes of the financial crisis. In fact, it's a distraction."

Petrou said the move could actually hurt the fight to curb too big to fail rather than help.

Lobbyists and political analysts warned the tax could get enacted, but said the bigger problem is the broader political frenzy feeding it.

"All bankers even those not affected directly by it should be very concerned about the renewed harsh rhetoric about banking," said Ed Yingling, president and CEO of the American Bankers Association. "The public doesn't necessarily hear all the distinctions and this type of rhetoric can be broadly harmful to the industry."

In announcing the program, President Obama took the public's side against the banks.

"We want our money back and we are going to get it," Obama said Thursday.

Late Wednesday, administration officials provided details of the plan rumored all week. Banks, thrifts, insurers and brokers with more than $50 billion in assets would have to pay a 15 basis point fee each year on so called net liabilities. Those would be calculated as an institution's assets minus its Tier One capital and insured deposits. The administration plans to ask Congress spread the fee over 10 years or longer, if necessary.

"This fee does target size and leverage," a senior administration official said. "Over 60% of the fees would be expected to be raised from the 10 largest financial institutions."

The official said the administration aims to recoup for taxpayers some $117 billion in expected losses on the government's bailout efforts.

About 50 firms will be covered, including 20 to 27 banking companies. About 35 of the total are expected to be U.S. companies and 10 to 15 U.S. arms of foreign firms.

Most analysts downplayed its potential effect.

Gerard Cassidy, an analyst at Royal Bank of Canada's RBC Capital Markets, conceded that the tax would over the long term hurt profitability and stock valuations. "But near term the bigger impact to earnings and stock prices will be the recovery in credit quality," he said.

"The potential bank tax is a silly idea in our opinion, but likely manageable," David George, an analyst at Robert W. Baird & Co., wrote in his note to clients. The tax "makes little sense and likely won't help lending or jobs," he added. That being said, the "expense burden may not be a disaster."

David Hendler, an analyst with CreditSights Inc., wrote in a report Thursday that the fee shows how "legislative risk" remains a "growing threat" to profits, even though most banks should be able to cover the fee relatively painlessly.

Some analysts even observed that the assessments appeared counterintuitive, with some of the lightest assessments planned for banks that benefited from large acquisitions in 2008 and 2009.

Carole Berger, an analyst at Luna Analytics LLC, wrote in a note to clients that Wells Fargo & Co. and PNC Financial Services Group Inc., were among the large banks with the least impact, likely taking an earnings hit of 5% of less.

In 2008, Wells bought Wachovia Corp. and PNC absorbed National City Corp. as those targets buckled under the financial crisis. Both acquirers also benefited from favorable tax treatments following their purchases.

Citigroup Inc., which failed in an effort to buy Wachovia's bank and grow its U.S. deposit base, will be dealt one of the harshest blows, analysts said. "The fee would be a big drag to Citi since they do not have a big deposit franchise and have very depressed earnings," Berger wrote.

Ryan estimated that Citi could have the third-biggest tax, at $1.37 billion. Wells, which emerged victorious in the battle over Wachovia, may face a hit of $454.4 million, Ryan projected.

The duration of the program also remains a topic of debate. While the general belief has been that banks could face the tax for 10 years, if not longer, some analysts are wondering if it would take that long for the government to recoup the costs of the Troubled Asset Relief Program.

Representatives at most banks in the crosshairs declined to comment, saying that they needed more time to assess the parameters and ultimate impact on their specific financial institution. With fourth-quarter conference calls looming, chief executives will be given little time to avoid the issue.

Despite the industry's opposition, it will be fighting an uphill political battle against it.

"You dismiss this proposal at your peril," said Jaret Seiberg, a political analyst at Concept Capital. "It is going to be very politically popular. The danger is it is going to gain so much momentum at the start that it is going to be difficult to stop."

The proposal will have an easier time passing the House, and many of its members came out in support of the tax on Thursday.

"President Obama's action today complies fully with the taxpayer protection language of the original TARP bill," House Financial Services Committee Chairman Barney Frank said. "His decision to do this before 2013 is a good one because there is no need to wait… I strongly support this proposal, and I am confident that the Committee on Ways and Means will be acting on it soon."

While it faces longer odds in the Senate, Banking Committee Chairman Chris Dodd also voiced his support.

"The president has it right," Dodd said. "Wall Street owes a great debt to the American public and we have the right and the obligation to recoup as much money as we can for the taxpayers. The taxpayers wrote the check that saved these firms. If it wasn't for the American taxpayers, they would just be empty offices."

But Republicans have been quick to oppose the idea, including Rep. Scott Garrett, R-.N.J., who said it would result in costs passed onto small businesses and companies' ability to produce jobs.

"History has shown that the most effective way to reinvigorate the economy and spur economic growth is to ensure that job creators face a lower tax and regulatory burden," he said. "The proposed bank fees will do just the opposite."

Matthew Monks and Cheyenne Hopkins contributed to this story