One measure of an effective politician – a real politician, not just an actor – is whether they can keep the promises they make. Or, perhaps whether they have an intention of doing so.

Consider Donald Trump, the Republican nominee for our country’s next President. In his speech accepting the Republican nomination and in previous venues, he has made numerous promises he can’t keep.

• He says he will build a wall between the United States and Mexico to keep immigrants out of this country – and that he will make Mexico pay for it. No way; building a wall would take millions, if not billions of dollars, and Mexico won’t ante up.

• He says he will make America safer again soon after taking the oath of office if he wins in November. No way, though the promise could be compelling. As President, he cannot compel action by independent, local police forces around the country, nor can he stop the violence those forces face.

• He says he will deport millions of “undocumented immigrants.” No way; he cannot afford the cost, nor the manpower to perform such a feat. The Wall Street Journal puts it this way: “executing on this promise would require at least $400 billion in new federal spending and reduce U.S. GDP by about $1 trillion. It also would require 90,000 federal agents, up from today’s 4,000.

• He says he will abandon NATO. No way. Congress won’t let him exercise this super power.

• He says he will constrict an independent press. No way. The Supreme Court won’t tolerate it.

• He says he wants to scrap all multi-national trade deals. No way. Perhaps those deals should have been developed with more of an “America first” stance, but scrapping them overnight can’t be done.

Make your own list. It would be a long one.

Trump’s Republican Convention performance, according to the Washington Post, was “more snarl and sneer, than substance.”

A good line to indicate, if nothing else, the wide range of Trump promises that he can’t keep unless he was a dictator, which, some say, is what he wants to be anyway.