The U.S has a far better military than Russia. I know one person might say" Russia will just lure them into colder weather" No, we just wait until they can't live out there anymore and they come back to us.
The war would devastating to both sides though. Millions of loss's
When we recently enacted those sanctions against Russia for the invasion of a sovereign nation, their economy tanked. When Europe began removing sanctions on their own, Russia was on the verge of collapse economically.
That being said, Russia would try and provoke some air battles over the Pacific Ocean and attempt to scare us up with some Central and South American nations pretending to be aggressive. When all is said and done, Putin would quickly need to choose between throwing out the white flag and surrendering or having his entire nation revolt against him when his economy collapses.
America tries to present itself to the world as a strong nation with strong army. All of it is lies and propaganda of the American nation. If Russia our fellow Slavic brother goes to war with USA, Serbia will make the Americans pay. We Serbs are supermen you cannot break the resolve of Serbs and we will crush your nation like a big under the Serbian boot nemanjic will be proud. Serbia + Russia = USA worst nightmare. Slavs fight three times better than weak Americans or English. America, if you do war Russia, you will feel the might of Serbian soldiers. Remove burger!!!
Loss of trade partner.
Loss of lives.
Loss of stunning amounts of money (for war effort.)
As America does not take the land it beats for itself, there is no benefit for them. Russia is not really hated by the other countries in the world, so USA would not even get their allies to appreciate them more. No advantages.
The United States does have many laudable advantages over the Russian military. Most notably we have an unmatched supremacy of carrier forces. But the Russian military boasts many cheaper, effective and conventional weapons that could turn the fight to their favor. The Pentagon has said as much recently stating that they are unsure that they would be able to maintain a sustained campaign against Russia. Our military's ground combat capabilities have been severely impacted and eroded by continuous deployments in Afghanistan and Iraq. Any action against Russia would put a strain on our stockpile of precision guided munitions, which was severely strained by the limited intervention into Libya.
Those two considerations aside, our air power is aging and is a shadow of what it was even 10 years ago. Many aircraft have been retired and the ones that have not are in dire need of structural and other updates to keep them combat relevant. Updates that have been put on the back burner in favor of the obscenely expensive and finally activated F-35 program.
Moreover getting back to the point of America's carrier monopoly, Russia is well prepared for this with their incredibly deadly Slava Class Guided Missile Cruisers. They possess 3 of these that each are capable of firing 16 SS-N-12 "Sandbox" missiles. These massive cruise missiles weigh five tons each and fly at a speed of mach 2.4. Needless to say a barrage of these missiles is more than enough to be a massive threat to American Carrier task forces. In addition to the strong surface to surface complement, the Slava class is equipped with 64 S-300 surface-to-air missiles that are more than capable of defending the Slava and it's task force from everything from a cruise missile to fighter aircraft. It also has 24 anti-submarine mortars and 10 torpedo tubes. Russia's entire naval doctrine is based on missiles fired en mass to overwhelm American carrier task forces.
That all being said there is no possible way to tell which side would prevail. Despite our belief in our technological superiority, we would not be guaranteed a victory over an admittedly weaker foe because of our depleted forces, Russia's commitment to hybrid warfare, and our logistical limitations operating in Eastern Europe.
The USA is the most aggressive country in the world so would straight away use all their planes and missiles bombarding Russia, Russia has the best anti air system in the world. The US would loose half its air force. The Large US navy would be pointless because its 2015 and boats are not much use against missiles. The US may be able to use them against Iraq but not Russia.
Then Russia would invade and using its Superior ground force (Tanks, AFV, Missile launchers, SPGs) which Russia out numbers the US in 2 to 1. Both countries would also take out there reserves and the US would not have that many more men than Russia. The Russians would take a few states and the US civilians would not be much help (1 in 4 are over wight ). The US would quickly surrender since it has no experience actually fighting a country with similar strength and instead enjoys getting half the world to help it attack a few rebels. The US has also never really defended. A quarter the people in the US hate their government anyway and would probably help the Russians.
Due to the US's lack of experience, lack of able fighters, lack of will and bad/aggressive tactics Russia would be Victories.