I think it is. China could send forces to Mexico and invade US from South with Billions of men. US would go down. American males don't know what sex they are and would run for Canada.
It is also from having an idiot in DC and a loss of faith In America as a leader.
US would need Soldiers on border 24/7 .
US would no longer have both friendly countries to the North or South.
I look for Canada to go pro China which would leave US isolated.
Since Biden took office the US has lost Mexico, Germany, France, most of South America, and India as allies. If world war 3 breaks out now it will be America , England, Canada (maybe) , Italy (maybe) Poland, and a few more Nato Countries. Germany and France will not help.