Read an interesting and pithy quote from a guy named Fukyomama (jokes his name is Fukuyama). Granted economics is not this simple but I do like the practical simplicity of it. With no further ado:
"Prior to the 1980s, conservatives were fiscally conservative— that is, they were unwilling to spend more than they collected in taxes. But Reaganomics introduced the idea that virtually any tax cut would so stimulate growth that the government would end up taking in more revenue in the end (the so-called Laffer curve). In fact, the traditional view was correct: if you cut taxes without cutting spending, you end up with a damaging deficit. Thus the Reagan tax cuts of the 1980s produced a big deficit; the Clinton tax increases of the 1990s produced a surplus; and the Bush tax cuts of the early 21st century produced an even larger deficit."