The Trump administration has been vocally supportive of increasing U.S. defense spending, which would be good news for military industrial giant Raytheon (NYSE: RTN). However, that doesn't necessarily mean the company's stock is worth buying now. Figuring that out requires a closer look at some of Raytheon's key valuation metrics. Here's what the numbers say.If you are looking at Raytheon, or any stock for that matter, it makes sense to go back to basics.