Like all arguments involving money and politics, the debate over American companies’ foreign-held cash and how it should be taxed – or not – when brought back to the U.S. quickly gets overheated and oversimplified.

Tuesday’s Congressional hearings, at which Apple Inc. (AAPL) chief executive Tim Cook is due to testify, will no doubt prove this.

Cook will argue, as leaders of big technology companies frequently do, that high official U.S. tax rates on foreign-sourced profits reduce the amount companies invest domestically in hiring and manufacturing.

Members of Sen. Carl Levin’s (D-Mich.) Permanent Subcommittee on Investigations are poised to pepper Cook with accusations that multinationals use accounting schemes to channel the maximum possible amount of profit through low-tax offshore jurisdictions as a massive tax-avoidance effort. (A 40-page memo released by the Subcommittee ahead of the testimony said as much.)

A reality in the middle

The reality, no surprise, is probably somewhere

The S&P 500 touched a new intraday high and the Nasdaq was briefly trading above 3,500 before reversing course to close slightly in the red. This after four straight weekly gains on the major indexes. It will be a light week for market-moving economic data, so traders may be more focused on the finale of earnings season which will see 27 S&P 500 companies reporting this week.

Yahoo! (YHOO) a the top attention-getter today on Wall Street as the company announced it's buying micro-blogging site Tumblr. Shares edged higher on the news of the plan. This will be Yahoo's seventh and biggest acquisition since Marissa Mayer became company CEO last July. The web portal will pay $1.1 billion dollars for Tumblr which boasts 108 million members and a very young user base with a high "cool factor."

Campbell Soup Co. (CPB) is hot, although investors seemed to cool to the stock today. Shares fell 4% despite the company beating on earnings. Excluding items, it posted profits of 62-cents a share when