Early Tuesday morning, at least 34 people were killed in Belgium in three terrorist attacks. Two struck the Zaventem airport, and one a subway station in central Brussels. It's a horrifying tragedy that should inspire solidarity with the Belgian people, and the victims of terrorism worldwide.

But in what has become a tiresomely predictable routine, some conservative politicians the world over immediately leveraged the attacks for advantage. Donald Trump pressed for more use of torture; both he and Ted Cruz called for overtly bigoted profiling of Muslim communities.

But perhaps a more telling reaction was the instinctive one from dozens of major cities across the globe, from Washington, D.C. to Moscow: tightening up security.

On the one hand, it's an understandable instinct from authorities who have little else to do in the immediate aftermath of a terrorist attack — though in the case of former DHS Secretary and current security consultant Michael Chertoff, who pushed for increased security at airports on CBS Tuesday morning, there may be simple monetary self-interest at work. But in any case, such moves are not going to accomplish much.

The point of security checkpoints at airports, for example, is to prevent terrorists from being able to hijack airlines or use them as weapons. (The Transportation Security Administration may be an abysmally incompetent money pit, but that's the idea and it's a reasonable one.) But another thing any checkpoint does is create a line of people who are waiting to get into the secure zone — and hence a potential target for someone looking to kill a bunch of innocent civilians. Witness the shooting at a checkpoint at the Los Angeles airport in 2013 that left one TSA officer dead and two others wounded. Similarly, the airport bombing in Brussels happened outside the security checkpoint.

The fundamental reality is that any free society is going to be inherently vulnerable to terrorist attacks. With basic civil liberties — freedom of movement, a right to privacy, due process, and so on — potential terrorists can slip in among the broader population fairly easily. There are millions of locations where people congregate, and there are hundreds of ways to make explosives out of the vast array of consumer goods available (and many more with materials that can be stolen). Hence, there are endless avenues available for someone who is determined to kill a ton of innocent people. That holds doubly true for the United States, awash as it is in hundreds of millions of firearms.

So while more security might be a prudent low-cost step for governments to take, we should not fool ourselves that it's going to seriously affect the overall level of security. Putting up checkpoints to enter a train or subway, as is often proposed during times like this, merely creates a mass of vulnerable civilians at a different place (and in any case misses the obvious move a smart terrorist would make, namely attacking the train from the outside while it's in motion).

Luckily for democratic societies, the number of people who would attempt terrorist attacks is extremely small. If there were more than a handful, then we would be suffering terrorist attacks on a weekly basis. Domestic anti-terror efforts should focus on bureaucratic competence, and quality police and intelligence work that is above all conducted without alienating masses of the population. Recruiting informants who are already part of terror cells is vital — sticking police spies into every mosque in the land, and thus breeding massive paranoia and resentment, is idiotic in the extreme.

Contra Trump and Cruz, there is no need to turn American into a racist police state — indeed it would probably make us less safe.