If it's gastritis (or an irritating of the stomach lining) or an ulcer, you'll most likely have a burning sensation in your upper abdomen that gets better or worse with eating. Take an OTC antacid such as Pepcid or Zantac, but if symptoms persist for more than a week, call your doctor.
The 2003 invasion of Iraq lasted from 20 March to 1 May 2003 and signalled the start of the Iraq War, which was dubbed Operation Iraqi Freedom by the United States (prior to 19 March, the mission in Iraq was called Operation Enduring Freedom, a carryover from the War in Afghanistan).
Another reason why the US led the invasion of Iraq in 2003 was that it presented a visible enemy. The US invasion of Afghanistan in October 2001 had led to the rapid collapse of the Taliban regime and the remainder of its fighters along with al-Qaeda had retreated into the tribal areas bordering Pakistan.