Why is the US Dollar lower than the euro ?

How does effect the us economy?
Should the US worry about this ?

Large budget and trade deficits since 2002, combined with a period of artificially low interest rates promoted by the Federal Reserve to stimulate the economy, have flooded the world markets with dollars, and have made it less desirable for foreign countries to hold dollars or dollar-denominated debt.

The lowering of the dollar's value makes US exports more affordable abroad and imports (and foreign travel) more expensive to Americans.

Although there are some global competitiveness benefits to US industries from the falling dollar, we should worry about it. As imports become more expensive, our standard of living decreases.