By Tim Montgomerie
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David Cameron paid very generous tribute to Barack Obama last night and it is understandable that he did. The chances are that the two men will be working with each other for a few more years yet if the Republicans don't find a quick solution to what is becoming a very messy nomination race. There'll also be a good number of Labour politicians back here in Britain who'll hate to see a British Prime Minister so close to the man they see as their ideological ally. Cameron and Obama do not appear the odd couple in the way that Bush and Blair did, however. Both men want to leave Afghanistan as soon as practically possible; they aren't that far apart on the size and scope of the state; both support gay marriage; and both want to avoid a military confrontation with Iran.

Osborne conservatives.comBut if Cameron's visit to the USA has won plaudits the Mail is unhappy that George Osborne went too. "This is the moment," it complains that the Chancellor chooses to "swan off to the U.S. for three days of saccharine photo opportunities and exchanges of platitudes with the Obamas." The newspaper argues that the economy is still very fragile. Today Fitch has joined Moody's in moving Britain to negative outlook. The head of the CBI tells The Times (£) that the Coalition is doing more regulating than deregulating. The CEO of British Airways accuses the Government of "warm words but cold action".

We all know what George Osborne thinks about deficit reduction but we don't know what he thinks about tax. Does he have a target overall level of tax in mind? Does he support more taxation of property and pollution to pay for less taxation of income and families? Does he favour co-payments such as road charging replacing some taxes? Does he want to eliminate individual taxes in every budget, as Nigel Lawson did? What does he think about so many more people paying the 40p income tax rate? Has he given up all of his 2005 interest in a flatter tax system? This vaccuum has become a dangerous place.

Aides to the Chancellor have told me not to fret about the Lib Dems doing all the public running on tax. The public won't remember what Lib Dems say, I'm reassured – the only thing the public will remember is what the Chancellor announces on Budget day. Perhaps but the Lib Dems are already owning credit for the £10,000 threshold policy. I fear they are also owning the wealth-verus-income tax debate.

In an important article in today's Financial Times (£), Paul Johnson of the Institute for Fiscal Studies warns that uncertainty about the shape of the UK tax system is very unhelpful to the economy: 

"The level of uncertainty created is unnecessary and destabilising. Changes to the taxation of property, pensions, capital gains and so on may be desirable. But annual speculation within a vacuum is damaging and costly. It’s time for Mr Osborne to show us where he stands."

Soon after the Budget Mr Osborne should give a big speech setting out his strategic thinking on tax. Taxpayers, business and Tory candidates could do with some clarity.