No, the discovery of a drug tunnel between the U.S. and Mexico does not support Trump's argument about Mexican immigrants. Trump says all Mexican immigrants are criminals, rapists and drug dealers. The tunnel is not necessarily used by immigrants. It is used by drug dealers, trying to move drugs across the border. The drugs are likely received by American dealers on the other side. The two things are not necessarily connected.
Trump is appealing to his base when he blames many of our country's problem on illegal immigration. The border can be tightened to prevent smuggling and US laws should be changed to decriminalize drugs and reduce the amount of illegal drugs that enter our country. Deporting millions of people is not the answer.
Donald Trump is wrong to claim Mexican immigrants are criminals, despite the discovery of a drug tunnel between Mexico and the United States. Many are hard working people that are simply looking for an opportunity for a better way of life. This is the same reason previous generations came into the country.
Few Mexican immigrants are involved in the drug trade and other such illegal activities. Many are just searching for a better life for themselves and their families. Evidence of a drug tunnel does not mean that Trump's stereotypes of Mexican immigrants are true. There is no evidence to support his claims.